-----BEGIN PGP SIGNATURE-----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=X4tZ
-----END PGP SIGNATURE-----
Merge 4.4.144 into android-4.4
Changes in 4.4.144
KVM/Eventfd: Avoid crash when assign and deassign specific eventfd in parallel.
x86/MCE: Remove min interval polling limitation
fat: fix memory allocation failure handling of match_strdup()
ALSA: rawmidi: Change resized buffers atomically
ARC: Fix CONFIG_SWAP
ARC: mm: allow mprotect to make stack mappings executable
mm: memcg: fix use after free in mem_cgroup_iter()
ipv4: Return EINVAL when ping_group_range sysctl doesn't map to user ns
ipv6: fix useless rol32 call on hash
lib/rhashtable: consider param->min_size when setting initial table size
net/ipv4: Set oif in fib_compute_spec_dst
net: phy: fix flag masking in __set_phy_supported
ptp: fix missing break in switch
tg3: Add higher cpu clock for 5762.
net: Don't copy pfmemalloc flag in __copy_skb_header()
skbuff: Unconditionally copy pfmemalloc in __skb_clone()
xhci: Fix perceived dead host due to runtime suspend race with event handler
x86/paravirt: Make native_save_fl() extern inline
x86/cpufeatures: Add CPUID_7_EDX CPUID leaf
x86/cpufeatures: Add Intel feature bits for Speculation Control
x86/cpufeatures: Add AMD feature bits for Speculation Control
x86/msr: Add definitions for new speculation control MSRs
x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown
x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes
x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support
x86/cpufeatures: Clean up Spectre v2 related CPUID flags
x86/cpuid: Fix up "virtual" IBRS/IBPB/STIBP feature bits on Intel
x86/pti: Mark constant arrays as __initconst
x86/asm/entry/32: Simplify pushes of zeroed pt_regs->REGs
x86/entry/64/compat: Clear registers for compat syscalls, to reduce speculation attack surface
x86/speculation: Update Speculation Control microcode blacklist
x86/speculation: Correct Speculation Control microcode blacklist again
x86/speculation: Clean up various Spectre related details
x86/speculation: Fix up array_index_nospec_mask() asm constraint
x86/speculation: Add <asm/msr-index.h> dependency
x86/xen: Zero MSR_IA32_SPEC_CTRL before suspend
x86/mm: Factor out LDT init from context init
x86/mm: Give each mm TLB flush generation a unique ID
x86/speculation: Use Indirect Branch Prediction Barrier in context switch
x86/spectre_v2: Don't check microcode versions when running under hypervisors
x86/speculation: Use IBRS if available before calling into firmware
x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPP
x86/speculation: Remove Skylake C2 from Speculation Control microcode blacklist
selftest/seccomp: Fix the flag name SECCOMP_FILTER_FLAG_TSYNC
selftest/seccomp: Fix the seccomp(2) signature
xen: set cpu capabilities from xen_start_kernel()
x86/amd: don't set X86_BUG_SYSRET_SS_ATTRS when running under Xen
x86/nospec: Simplify alternative_msr_write()
x86/bugs: Concentrate bug detection into a separate function
x86/bugs: Concentrate bug reporting into a separate function
x86/bugs: Read SPEC_CTRL MSR during boot and re-use reserved bits
x86/bugs, KVM: Support the combination of guest and host IBRS
x86/cpu: Rename Merrifield2 to Moorefield
x86/cpu/intel: Add Knights Mill to Intel family
x86/bugs: Expose /sys/../spec_store_bypass
x86/cpufeatures: Add X86_FEATURE_RDS
x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigation
x86/bugs/intel: Set proper CPU features and setup RDS
x86/bugs: Whitelist allowed SPEC_CTRL MSR values
x86/bugs/AMD: Add support to disable RDS on Fam[15, 16, 17]h if requested
x86/speculation: Create spec-ctrl.h to avoid include hell
prctl: Add speculation control prctls
x86/process: Optimize TIF checks in __switch_to_xtra()
x86/process: Correct and optimize TIF_BLOCKSTEP switch
x86/process: Optimize TIF_NOTSC switch
x86/process: Allow runtime control of Speculative Store Bypass
x86/speculation: Add prctl for Speculative Store Bypass mitigation
nospec: Allow getting/setting on non-current task
proc: Provide details on speculation flaw mitigations
seccomp: Enable speculation flaw mitigations
prctl: Add force disable speculation
seccomp: Use PR_SPEC_FORCE_DISABLE
seccomp: Add filter flag to opt-out of SSB mitigation
seccomp: Move speculation migitation control to arch code
x86/speculation: Make "seccomp" the default mode for Speculative Store Bypass
x86/bugs: Rename _RDS to _SSBD
proc: Use underscores for SSBD in 'status'
Documentation/spec_ctrl: Do some minor cleanups
x86/bugs: Fix __ssb_select_mitigation() return type
x86/bugs: Make cpu_show_common() static
x86/bugs: Fix the parameters alignment and missing void
x86/cpu: Make alternative_msr_write work for 32-bit code
x86/speculation: Use synthetic bits for IBRS/IBPB/STIBP
x86/cpufeatures: Disentangle MSR_SPEC_CTRL enumeration from IBRS
x86/cpufeatures: Disentangle SSBD enumeration
x86/cpu/AMD: Fix erratum 1076 (CPB bit)
x86/cpufeatures: Add FEATURE_ZEN
x86/speculation: Handle HT correctly on AMD
x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRL
x86/speculation: Add virtualized speculative store bypass disable support
x86/speculation: Rework speculative_store_bypass_update()
x86/bugs: Unify x86_spec_ctrl_{set_guest, restore_host}
x86/bugs: Expose x86_spec_ctrl_base directly
x86/bugs: Remove x86_spec_ctrl_set()
x86/bugs: Rework spec_ctrl base and mask logic
x86/speculation, KVM: Implement support for VIRT_SPEC_CTRL/LS_CFG
x86/bugs: Rename SSBD_NO to SSB_NO
x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths
x86/cpu: Re-apply forced caps every time CPU caps are re-read
block: do not use interruptible wait anywhere
clk: tegra: Fix PLL_U post divider and initial rate on Tegra30
ubi: Introduce vol_ignored()
ubi: Rework Fastmap attach base code
ubi: Be more paranoid while seaching for the most recent Fastmap
ubi: Fix races around ubi_refill_pools()
ubi: Fix Fastmap's update_vol()
ubi: fastmap: Erase outdated anchor PEBs during attach
Linux 4.4.144
Change-Id: Ia3e9b2b7bc653cba68b76878d34f8fcbbc007a13
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 356e4bfff2c5489e016fdb925adbf12a1e3950ee upstream
For certain use cases it is desired to enforce mitigations so they cannot
be undone afterwards. That's important for loader stubs which want to
prevent a child from disabling the mitigation again. Will also be used for
seccomp(). The extra state preserving of the prctl state for SSB is a
preparatory step for EBPF dymanic speculation control.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com>
Reviewed-by: Alexey Makhalov <amakhalov@vmware.com>
Reviewed-by: Bo Gan <ganb@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add time in state data to task structs, and create
/proc/<pid>/time_in_state files to show how long each individual task
has run at each frequency.
Create a CONFIG_CPU_FREQ_TIMES option to enable/disable this tracking.
Signed-off-by: Connor O'Brien <connoro@google.com>
Bug: 72339335
Test: Read /proc/<pid>/time_in_state
Change-Id: Ia6456754f4cb1e83b2bc35efa8fbe9f8696febc8
We need to call exit_thread from copy_process in a fail path. So make it
accept task_struct as a parameter.
[v2]
* s390: exit_thread_runtime_instr doesn't make sense to be called for
non-current tasks.
* arm: fix the comment in vfp_thread_copy
* change 'me' to 'tsk' for task_struct
* now we can change only archs that actually have exit_thread
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Howells <dhowells@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit e64646946ed32902fd597fa6e514b1da84642de3)
Conflicts:
arch/s390/kernel/process.c
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Boosted RT tasks can be deboosted quickly, this makes boost usless
for RT tasks and causes lots of glitching. Use timers to prevent
de-boost too soon and wait for long enough such that next enqueue
happens after a threshold.
While this can be solved in the governor, there are following
advantages:
- The approach used is governor-independent
- Reduces boost group lock contention for frequently sleepers/wakers
Note:
Fixed build breakage due to schedfreq dependency which isn't used
for RT anymore.
Bug: 30210506
Change-Id: I428a2695cac06cc3458cdde0dea72315e4e66c00
Signed-off-by: Joel Fernandes <joelaf@google.com>
-----BEGIN PGP SIGNATURE-----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=vx5p
-----END PGP SIGNATURE-----
Merge 4.4.114 into android-4.4
Changes in 4.4.114
x86/asm/32: Make sync_core() handle missing CPUID on all 32-bit kernels
usbip: prevent vhci_hcd driver from leaking a socket pointer address
usbip: Fix implicit fallthrough warning
usbip: Fix potential format overflow in userspace tools
x86/microcode/intel: Fix BDW late-loading revision check
x86/cpu/intel: Introduce macros for Intel family numbers
x86/retpoline: Fill RSB on context switch for affected CPUs
sched/deadline: Use the revised wakeup rule for suspending constrained dl tasks
can: af_can: can_rcv(): replace WARN_ONCE by pr_warn_once
can: af_can: canfd_rcv(): replace WARN_ONCE by pr_warn_once
PM / sleep: declare __tracedata symbols as char[] rather than char
time: Avoid undefined behaviour in ktime_add_safe()
timers: Plug locking race vs. timer migration
Prevent timer value 0 for MWAITX
drivers: base: cacheinfo: fix x86 with CONFIG_OF enabled
drivers: base: cacheinfo: fix boot error message when acpi is enabled
PCI: layerscape: Add "fsl,ls2085a-pcie" compatible ID
PCI: layerscape: Fix MSG TLP drop setting
mmc: sdhci-of-esdhc: add/remove some quirks according to vendor version
fs/select: add vmalloc fallback for select(2)
mm/mmap.c: do not blow on PROT_NONE MAP_FIXED holes in the stack
hwpoison, memcg: forcibly uncharge LRU pages
cma: fix calculation of aligned offset
mm, page_alloc: fix potential false positive in __zone_watermark_ok
ipc: msg, make msgrcv work with LONG_MIN
x86/ioapic: Fix incorrect pointers in ioapic_setup_resources()
ACPI / processor: Avoid reserving IO regions too early
ACPI / scan: Prefer devices without _HID/_CID for _ADR matching
ACPICA: Namespace: fix operand cache leak
netfilter: x_tables: speed up jump target validation
netfilter: arp_tables: fix invoking 32bit "iptable -P INPUT ACCEPT" failed in 64bit kernel
netfilter: nf_dup_ipv6: set again FLOWI_FLAG_KNOWN_NH at flowi6_flags
netfilter: nf_ct_expect: remove the redundant slash when policy name is empty
netfilter: nfnetlink_queue: reject verdict request from different portid
netfilter: restart search if moved to other chain
netfilter: nf_conntrack_sip: extend request line validation
netfilter: use fwmark_reflect in nf_send_reset
netfilter: fix IS_ERR_VALUE usage
netfilter: nfnetlink_cthelper: Add missing permission checks
netfilter: xt_osf: Add missing permission checks
ext2: Don't clear SGID when inheriting ACLs
reiserfs: fix race in prealloc discard
reiserfs: don't preallocate blocks for extended attributes
reiserfs: Don't clear SGID when inheriting ACLs
fs/fcntl: f_setown, avoid undefined behaviour
scsi: libiscsi: fix shifting of DID_REQUEUE host byte
Revert "module: Add retpoline tag to VERMAGIC"
Input: trackpoint - force 3 buttons if 0 button is reported
usb: usbip: Fix possible deadlocks reported by lockdep
usbip: fix stub_rx: get_pipe() to validate endpoint number
usbip: fix stub_rx: harden CMD_SUBMIT path to handle malicious input
usbip: prevent leaking socket pointer address in messages
um: link vmlinux with -no-pie
vsyscall: Fix permissions for emulate mode with KAISER/PTI
eventpoll.h: add missing epoll event masks
x86/microcode/intel: Extend BDW late-loading further with LLC size check
hrtimer: Reset hrtimer cpu base proper on CPU hotplug
dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
ipv6: Fix getsockopt() for sockets with default IPV6_AUTOFLOWLABEL
ipv6: fix udpv6 sendmsg crash caused by too small MTU
ipv6: ip6_make_skb() needs to clear cork.base.dst
lan78xx: Fix failure in USB Full Speed
net: igmp: fix source address check for IGMPv3 reports
tcp: __tcp_hdrlen() helper
net: qdisc_pkt_len_init() should be more robust
pppoe: take ->needed_headroom of lower device into account on xmit
r8169: fix memory corruption on retrieval of hardware statistics.
sctp: do not allow the v4 socket to bind a v4mapped v6 address
sctp: return error if the asoc has been peeled off in sctp_wait_for_sndbuf
vmxnet3: repair memory leak
net: Allow neigh contructor functions ability to modify the primary_key
ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY
flow_dissector: properly cap thoff field
net: tcp: close sock if net namespace is exiting
nfsd: auth: Fix gid sorting when rootsquash enabled
Linux 4.4.114
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 3effcb4247e74a51f5d8b775a1ee4abf87cc089a upstream.
We have been facing some problems with self-suspending constrained
deadline tasks. The main reason is that the original CBS was not
designed for such sort of tasks.
One problem reported by Xunlei Pang takes place when a task
suspends, and then is awakened before the deadline, but so close
to the deadline that its remaining runtime can cause the task
to have an absolute density higher than allowed. In such situation,
the original CBS assumes that the task is facing an early activation,
and so it replenishes the task and set another deadline, one deadline
in the future. This rule works fine for implicit deadline tasks.
Moreover, it allows the system to adapt the period of a task in which
the external event source suffered from a clock drift.
However, this opens the window for bandwidth leakage for constrained
deadline tasks. For instance, a task with the following parameters:
runtime = 5 ms
deadline = 7 ms
[density] = 5 / 7 = 0.71
period = 1000 ms
If the task runs for 1 ms, and then suspends for another 1ms,
it will be awakened with the following parameters:
remaining runtime = 4
laxity = 5
presenting a absolute density of 4 / 5 = 0.80.
In this case, the original CBS would assume the task had an early
wakeup. Then, CBS will reset the runtime, and the absolute deadline will
be postponed by one relative deadline, allowing the task to run.
The problem is that, if the task runs this pattern forever, it will keep
receiving bandwidth, being able to run 1ms every 2ms. Following this
behavior, the task would be able to run 500 ms in 1 sec. Thus running
more than the 5 ms / 1 sec the admission control allowed it to run.
Trying to address the self-suspending case, Luca Abeni, Giuseppe
Lipari, and Juri Lelli [1] revisited the CBS in order to deal with
self-suspending tasks. In the new approach, rather than
replenishing/postponing the absolute deadline, the revised wakeup rule
adjusts the remaining runtime, reducing it to fit into the allowed
density.
A revised version of the idea is:
At a given time t, the maximum absolute density of a task cannot be
higher than its relative density, that is:
runtime / (deadline - t) <= dl_runtime / dl_deadline
Knowing the laxity of a task (deadline - t), it is possible to move
it to the other side of the equality, thus enabling to define max
remaining runtime a task can use within the absolute deadline, without
over-running the allowed density:
runtime = (dl_runtime / dl_deadline) * (deadline - t)
For instance, in our previous example, the task could still run:
runtime = ( 5 / 7 ) * 5
runtime = 3.57 ms
Without causing damage for other deadline tasks. It is note worthy
that the laxity cannot be negative because that would cause a negative
runtime. Thus, this patch depends on the patch:
df8eac8cafce ("sched/deadline: Throttle a constrained deadline task activated after the deadline")
Which throttles a constrained deadline task activated after the
deadline.
Finally, it is also possible to use the revised wakeup rule for
all other tasks, but that would require some more discussions
about pros and cons.
[The main difference from the original commit is that
the BW_SHIFT define was not present yet. As BW_SHIFT was
introduced in a new feature, I just used the value (20),
likewise we used to use before the #define.
Other changes were required because of comments. - bistrot]
Reported-by: Xunlei Pang <xpang@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
[peterz: replaced dl_is_constrained with dl_is_implicit]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luca Abeni <luca.abeni@santannapisa.it>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Romulo Silva de Oliveira <romulo.deoliveira@ufsc.br>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tommaso Cucinotta <tommaso.cucinotta@sssup.it>
Link: http://lkml.kernel.org/r/5c800ab3a74a168a84ee5f3f84d12a02e11383be.1495803804.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing). Coverage-guided fuzzing is a testing technique
that uses coverage feedback to determine new interesting inputs to a
system. A notable user-space example is AFL
(http://lcamtuf.coredump.cx/afl/). However, this technique is not
widely used for kernel testing due to missing compiler and kernel
support.
kcov does not aim to collect as much coverage as possible. It aims to
collect more or less stable coverage that is function of syscall inputs.
To achieve this goal it does not collect coverage in soft/hard
interrupts and instrumentation of some inherently non-deterministic or
non-interesting parts of kernel is disbled (e.g. scheduler, locking).
Currently there is a single coverage collection mode (tracing), but the
API anticipates additional collection modes. Initially I also
implemented a second mode which exposes coverage in a fixed-size hash
table of counters (what Quentin used in his original patch). I've
dropped the second mode for simplicity.
This patch adds the necessary support on kernel side. The complimentary
compiler support was added in gcc revision 231296.
We've used this support to build syzkaller system call fuzzer, which has
found 90 kernel bugs in just 2 months:
https://github.com/google/syzkaller/wiki/Found-Bugs
We've also found 30+ bugs in our internal systems with syzkaller.
Another (yet unexplored) direction where kcov coverage would greatly
help is more traditional "blob mutation". For example, mounting a
random blob as a filesystem, or receiving a random blob over wire.
Why not gcov. Typical fuzzing loop looks as follows: (1) reset
coverage, (2) execute a bit of code, (3) collect coverage, repeat. A
typical coverage can be just a dozen of basic blocks (e.g. an invalid
input). In such context gcov becomes prohibitively expensive as
reset/collect coverage steps depend on total number of basic
blocks/edges in program (in case of kernel it is about 2M). Cost of
kcov depends only on number of executed basic blocks/edges. On top of
that, kernel requires per-thread coverage because there are always
background threads and unrelated processes that also produce coverage.
With inlined gcov instrumentation per-thread coverage is not possible.
kcov exposes kernel PCs and control flow to user-space which is
insecure. But debugfs should not be mapped as user accessible.
Based on a patch by Quentin Casasnovas.
[akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode']
[akpm@linux-foundation.org: unbreak allmodconfig]
[akpm@linux-foundation.org: follow x86 Makefile layout standards]
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tavis Ormandy <taviso@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@google.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: David Drysdale <drysdale@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bug: 64145065
(cherry-picked from 5c9a8750a6409c63a0f01d51a9024861022f6593)
Change-Id: I17b5e04f6e89b241924e78ec32ead79c38b860ce
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Boosted RT tasks can be deboosted quickly, this makes boost usless
for RT tasks and causes lots of glitching. Use timers to prevent
de-boost too soon and wait for long enough such that next enqueue
happens after a threshold.
While this can be solved in the governor, there are following
advantages:
- The approach used is governor-independent
- Reduces boost group lock contention for frequently sleepers/wakers
- Works with schedfreq without any other schedfreq hacks.
Bug: 30210506
Change-Id: I41788b235586988be446505deb7c0529758a9898
Signed-off-by: Joel Fernandes <joelaf@google.com>
(from https://patchwork.kernel.org/patch/9895261/)
This patch adds a parameter to select_task_rq, sibling_count_hint
allowing the caller, where it has this information, to inform the
sched_class the number of tasks that are being woken up as part of
the same event.
The wake_q mechanism is one case where this information is available.
select_task_rq_fair can then use the information to detect that it
needs to widen the search space for task placement in order to avoid
overloading the last-level cache domain's CPUs.
* * *
The reason I am investigating this change is the following use case
on ARM big.LITTLE (asymmetrical CPU capacity): 1 task per CPU, which
all repeatedly do X amount of work then
pthread_barrier_wait (i.e. sleep until the last task finishes its X
and hits the barrier). On big.LITTLE, the tasks which get a "big" CPU
finish faster, and then those CPUs pull over the tasks that are still
running:
v CPU v ->time->
-------------
0 (big) 11111 /333
-------------
1 (big) 22222 /444|
-------------
2 (LITTLE) 333333/
-------------
3 (LITTLE) 444444/
-------------
Now when task 4 hits the barrier (at |) and wakes the others up,
there are 4 tasks with prev_cpu=<big> and 0 tasks with
prev_cpu=<little>. want_affine therefore means that we'll only look
in CPUs 0 and 1 (sd_llc), so tasks will be unnecessarily coscheduled
on the bigs until the next load balance, something like this:
v CPU v ->time->
------------------------
0 (big) 11111 /333 31313\33333
------------------------
1 (big) 22222 /444|424\4444444
------------------------
2 (LITTLE) 333333/ \222222
------------------------
3 (LITTLE) 444444/ \1111
------------------------
^^^
underutilization
So, I'm trying to get want_affine = 0 for these tasks.
I don't _think_ any incarnation of the wakee_flips mechanism can help
us here because which task is waker and which tasks are wakees
generally changes with each iteration.
However pthread_barrier_wait (or more accurately FUTEX_WAKE) has the
nice property that we know exactly how many tasks are being woken, so
we can cheat.
It might be a disadvantage that we "widen" _every_ task that's woken in
an event, while select_idle_sibling would work fine for the first
sd_llc_size - 1 tasks.
IIUC, if wake_affine() behaves correctly this trick wouldn't be
necessary on SMP systems, so it might be best guarded by the presence
of SD_ASYM_CPUCAPACITY?
* * *
Final note..
In order to observe "perfect" behaviour for this use case, I also had
to disable the TTWU_QUEUE sched feature. Suppose during the wakeup
above we are working through the work queue and have placed tasks 3
and 2, and are about to place task 1:
v CPU v ->time->
--------------
0 (big) 11111 /333 3
--------------
1 (big) 22222 /444|4
--------------
2 (LITTLE) 333333/ 2
--------------
3 (LITTLE) 444444/ <- Task 1 should go here
--------------
If TTWU_QUEUE is enabled, we will not yet have enqueued task
2 (having instead sent a reschedule IPI) or attached its load to CPU
2. So we are likely to also place task 1 on cpu 2. Disabling
TTWU_QUEUE means that we enqueue task 2 before placing task 1,
solving this issue. TTWU_QUEUE is there to minimise rq lock
contention, and I guess that this contention is less of an issue on
big.LITTLE systems since they have relatively few CPUs, which
suggests the trade-off makes sense here.
Change-Id: I2080302839a263e0841a89efea8589ea53bbda9c
Signed-off-by: Brendan Jackman <brendan.jackman@arm.com>
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Energy cost estimation has been a long lasting challenge for WALT
because WALT guides CPU frequency based on the CPU utilization of
previous window. Consequently it's not possible to know newly
waking-up task's energy cost until WALT's end of the current window.
The WALT already tracks 'Previous Runnable Sum' (prev_runnable_sum)
and 'Cumulative Runnable Average' (cr_avg). They are designed for
CPU frequency guidance and task placement but unfortunately both
are not suitable for the energy cost estimation.
It's because using prev_runnable_sum for energy cost calculation would
make us to account CPU and task's energy solely based on activity in the
previous window so for example, any task didn't have an activity in the
previous window will be accounted as a 'zero energy cost' task.
Energy estimation with cr_avg is what energy_diff() relies on at present.
However cr_avg can only represent instantaneous picture of energy cost
thus for example, if a CPU was fully occupied for an entire WALT window
and became idle just before window boundary, and if there is a wake-up,
energy_diff() accounts that CPU is a 'zero energy cost' CPU.
As a result, introduce a new accounting unit 'Cumulative Window Demand'.
The cumulative window demand tracks all the tasks' demands have seen in
current window which is neither instantaneous nor actual execution time.
Because task demand represents estimated scaled execution time when the
task runs a full window, accumulation of all the demands represents
predicted CPU load at the end of window.
Thus we can estimate CPU's frequency at the end of current WALT window
with the cumulative window demand.
The use of prev_runnable_sum for the CPU frequency guidance and cr_avg
for the task placement have not changed and these are going to be used
for both purpose while this patch aims to add an additional statistics.
Change-Id: I9908c77ead9973a26dea2b36c001c2baf944d4f5
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
Vincent and Yuyang found another few scenarios in which entity
tracking goes wobbly.
The scenarios are basically due to the fact that new tasks are not
immediately attached and thereby differ from the normal situation -- a
task is always attached to a cfs_rq load average (such that it
includes its blocked contribution) and are explicitly
detached/attached on migration to another cfs_rq.
Scenario 1: switch to fair class
p->sched_class = fair_class;
if (queued)
enqueue_task(p);
...
enqueue_entity()
enqueue_entity_load_avg()
migrated = !sa->last_update_time (true)
if (migrated)
attach_entity_load_avg()
check_class_changed()
switched_from() (!fair)
switched_to() (fair)
switched_to_fair()
attach_entity_load_avg()
If @p is a new task that hasn't been fair before, it will have
!last_update_time and, per the above, end up in
attach_entity_load_avg() _twice_.
Scenario 2: change between cgroups
sched_move_group(p)
if (queued)
dequeue_task()
task_move_group_fair()
detach_task_cfs_rq()
detach_entity_load_avg()
set_task_rq()
attach_task_cfs_rq()
attach_entity_load_avg()
if (queued)
enqueue_task();
...
enqueue_entity()
enqueue_entity_load_avg()
migrated = !sa->last_update_time (true)
if (migrated)
attach_entity_load_avg()
Similar as with scenario 1, if @p is a new task, it will have
!load_update_time and we'll end up in attach_entity_load_avg()
_twice_.
Furthermore, notice how we do a detach_entity_load_avg() on something
that wasn't attached to begin with.
As stated above; the problem is that the new task isn't yet attached
to the load tracking and thereby violates the invariant assumption.
This patch remedies this by ensuring a new task is indeed properly
attached to the load tracking on creation, through
post_init_entity_util_avg().
Of course, this isn't entirely as straightforward as one might think,
since the task is hashed before we call wake_up_new_task() and thus
can be poked at. We avoid this by adding TASK_NEW and teaching
cpu_cgroup_can_attach() to refuse such tasks.
.:: BACKPORT
Complicated by the fact that mch of the lines changed by the original
of this commit were then changed by:
df217913e72e sched/fair: Factorize attach/detach entity <Vincent Guittot>
and then
d31b1a66cbe0 sched/fair: Factorize PELT update <Vincent Guittot>
, which have both already been backported here.
Reported-by: Yuyang Du <yuyang.du@intel.com>
Reported-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 7dc603c9028ea5d4354e0e317e8481df99b06d7e)
Change-Id: Ibc59eb52310a62709d49a744bd5a24e8b97c4ae8
Signed-off-by: Brendan Jackman <brendan.jackman@arm.com>
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
(cherry picked from commit ec8d7c14ea14922fe21945b458a75e39f11dd832)
Tetsuo has properly noted that mmput slow path might get blocked waiting
for another party (e.g. exit_aio waits for an IO). If that happens the
oom_reaper would be put out of the way and will not be able to process
next oom victim. We should strive for making this context as reliable
and independent on other subsystems as much as possible.
Introduce mmput_async which will perform the slow path from an async
(WQ) context. This will delay the operation but that shouldn't be a
problem because the oom_reaper has reclaimed the victim's address space
for most cases as much as possible and the remaining context shouldn't
bind too much memory anymore. The only exception is when mmap_sem
trylock has failed which shouldn't happen too often.
The issue is only theoretical but not impossible.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Only backports mmput_async.
Change-Id: I5fe54abcc629e7d9eab9fe03908903d1174177f1
Signed-off-by: Arve Hjønnevåg <arve@android.com>
-----BEGIN PGP SIGNATURE-----
iQIzBAABCAAdFiEEZH8oZUiU471FcZm+ONu9yGCSaT4FAlmfaTcACgkQONu9yGCS
aT65LhAAlTz6ssLhstl1QhFIUZ5cTIMouONCYK2+fwg67J3nf8I4whaj0eXX9RIT
4f6L1JNn3YV6lEfXZLs3EHeiMWft2cal95yQULwhsSwI/1rAzjYkFtj59gPxp2Rc
03ZrU8UnWNZmKpzneiwnd0kkFi+7wBKT5GbERy6Voh1hpAg8HbHQeWdVxFXKCdLD
eSP1+RNsvknZBjcJibxhsArs8E8r5t+dXDzi0HYpiZvctV23VXD+y2UDE1RMEDx5
k5fH30DIxd3T1JU1qHGnJUlfK5jKVho76zoSThwEFm9xqoZat/xrby5gW5sMcWeD
0BMw4F6GYE8BoeViC/+iujR0B8ngU0e+ExH+M6WYoEGPH1BFHyPNqDoKjnyAjyyH
tQEOD/0aRWuxcBVyk34EafNZeou/AeDd0IReAHciCIomN0+3u104+HlxkGH1oXEn
u0O5kVXQPaB/YeXd3jRLSfDmzxojaaihTeJZGFi//1iAj+jJEeYagfeI+flqrtaC
Gcwi55HrNrLbEj9kBFLEnm8RgFyWFsO0oVbfu1bPUGZOmuMi4u1Ptkffi3p/Wrsh
cx9ErKXj6meOgkcmzCWYl1Ygp3rY3bdlbidixJnzEfOTeZ2FyxnMz3BQAxGeOPTD
OhUevEK08oMTb1YDt3i7Sh1BGKpU0AEaEw5i8m36m4rC6KdqJfA=
=JeJw
-----END PGP SIGNATURE-----
Merge 4.4.84 into android-4.4
Changes in 4.4.84
netfilter: nf_ct_ext: fix possible panic after nf_ct_extend_unregister
audit: Fix use after free in audit_remove_watch_rule()
parisc: pci memory bar assignment fails with 64bit kernels on dino/cujo
crypto: x86/sha1 - Fix reads beyond the number of blocks passed
Input: elan_i2c - add ELAN0608 to the ACPI table
Input: elan_i2c - Add antoher Lenovo ACPI ID for upcoming Lenovo NB
ALSA: seq: 2nd attempt at fixing race creating a queue
ALSA: usb-audio: Apply sample rate quirk to Sennheiser headset
ALSA: usb-audio: Add mute TLV for playback volumes on C-Media devices
mm/mempolicy: fix use after free when calling get_mempolicy
mm: revert x86_64 and arm64 ELF_ET_DYN_BASE base changes
xen: fix bio vec merging
x86/asm/64: Clear AC on NMI entries
irqchip/atmel-aic: Fix unbalanced of_node_put() in aic_common_irq_fixup()
irqchip/atmel-aic: Fix unbalanced refcount in aic_common_rtc_irq_fixup()
Sanitize 'move_pages()' permission checks
pids: make task_tgid_nr_ns() safe
perf/x86: Fix LBR related crashes on Intel Atom
usb: optimize acpi companion search for usb port devices
usb: qmi_wwan: add D-Link DWM-222 device ID
Linux 4.4.84
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit dd1c1f2f2028a7b851f701fc6a8ebe39dcb95e7c upstream.
This was reported many times, and this was even mentioned in commit
52ee2dfdd4 ("pids: refactor vnr/nr_ns helpers to make them safe") but
somehow nobody bothered to fix the obvious problem: task_tgid_nr_ns() is
not safe because task->group_leader points to nowhere after the exiting
task passes exit_notify(), rcu_read_lock() can not help.
We really need to change __unhash_process() to nullify group_leader,
parent, and real_parent, but this needs some cleanups. Until then we
can turn task_tgid_nr_ns() into another user of __task_pid_nr_ns() and
fix the problem.
Reported-by: Troy Kensinger <tkensinger@google.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----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=pHqB
-----END PGP SIGNATURE-----
Merge 4.4.81 into android-4.4
Changes in 4.4.81
libata: array underflow in ata_find_dev()
workqueue: restore WQ_UNBOUND/max_active==1 to be ordered
ALSA: hda - Fix speaker output from VAIO VPCL14M1R
ASoC: do not close shared backend dailink
KVM: async_pf: make rcu irq exit if not triggered from idle task
mm/page_alloc: Remove kernel address exposure in free_reserved_area()
ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize
ext4: fix overflow caused by missing cast in ext4_resize_fs()
ARM: dts: armada-38x: Fix irq type for pca955
media: platform: davinci: return -EINVAL for VPFE_CMD_S_CCDC_RAW_PARAMS ioctl
target: Avoid mappedlun symlink creation during lun shutdown
iscsi-target: Always wait for kthread_should_stop() before kthread exit
iscsi-target: Fix early sk_data_ready LOGIN_FLAGS_READY race
iscsi-target: Fix initial login PDU asynchronous socket close OOPs
iscsi-target: Fix delayed logout processing greater than SECONDS_FOR_LOGOUT_COMP
iser-target: Avoid isert_conn->cm_id dereference in isert_login_recv_done
mm, mprotect: flush TLB if potentially racing with a parallel reclaim leaving stale TLB entries
media: lirc: LIRC_GET_REC_RESOLUTION should return microseconds
f2fs: sanity check checkpoint segno and blkoff
drm: rcar-du: fix backport bug
saa7164: fix double fetch PCIe access condition
ipv4: ipv6: initialize treq->txhash in cookie_v[46]_check()
net: Zero terminate ifr_name in dev_ifname().
ipv6: avoid overflow of offset in ip6_find_1stfragopt
ipv4: initialize fib_trie prior to register_netdev_notifier call.
rtnetlink: allocate more memory for dev_set_mac_address()
mcs7780: Fix initialization when CONFIG_VMAP_STACK is enabled
openvswitch: fix potential out of bound access in parse_ct
packet: fix use-after-free in prb_retire_rx_blk_timer_expired()
ipv6: Don't increase IPSTATS_MIB_FRAGFAILS twice in ip6_fragment()
net: ethernet: nb8800: Handle all 4 RGMII modes identically
dccp: fix a memleak that dccp_ipv6 doesn't put reqsk properly
dccp: fix a memleak that dccp_ipv4 doesn't put reqsk properly
dccp: fix a memleak for dccp_feat_init err process
sctp: don't dereference ptr before leaving _sctp_walk_{params, errors}()
sctp: fix the check for _sctp_walk_params and _sctp_walk_errors
net/mlx5: Fix command bad flow on command entry allocation failure
net: phy: Correctly process PHY_HALTED in phy_stop_machine()
net: phy: Fix PHY unbind crash
xen-netback: correctly schedule rate-limited queues
sparc64: Measure receiver forward progress to avoid send mondo timeout
wext: handle NULL extra data in iwe_stream_add_point better
sh_eth: R8A7740 supports packet shecksumming
net: phy: dp83867: fix irq generation
tg3: Fix race condition in tg3_get_stats64().
x86/boot: Add missing declaration of string functions
phy state machine: failsafe leave invalid RUNNING state
scsi: qla2xxx: Get mutex lock before checking optrom_state
drm/virtio: fix framebuffer sparse warning
virtio_blk: fix panic in initialization error path
ARM: 8632/1: ftrace: fix syscall name matching
mm, slab: make sure that KMALLOC_MAX_SIZE will fit into MAX_ORDER
lib/Kconfig.debug: fix frv build failure
signal: protect SIGNAL_UNKILLABLE from unintentional clearing.
mm: don't dereference struct page fields of invalid pages
ipv4: Should use consistent conditional judgement for ip fragment in __ip_append_data and ip_finish_output
net: account for current skb length when deciding about UFO
workqueue: implicit ordered attribute should be overridable
Linux 4.4.81
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
[ Upstream commit 2d39b3cd34e6d323720d4c61bd714f5ae202c022 ]
Since commit 00cd5c37af ("ptrace: permit ptracing of /sbin/init") we
can now trace init processes. init is initially protected with
SIGNAL_UNKILLABLE which will prevent fatal signals such as SIGSTOP, but
there are a number of paths during tracing where SIGNAL_UNKILLABLE can
be implicitly cleared.
This can result in init becoming stoppable/killable after tracing. For
example, running:
while true; do kill -STOP 1; done &
strace -p 1
and then stopping strace and the kill loop will result in init being
left in state TASK_STOPPED. Sending SIGCONT to init will resume it, but
init will now respond to future SIGSTOP signals rather than ignoring
them.
Make sure that when setting SIGNAL_STOP_CONTINUED/SIGNAL_STOP_STOPPED
that we don't clear SIGNAL_UNKILLABLE.
Link: http://lkml.kernel.org/r/20170104122017.25047-1-jamie.iles@oracle.com
Signed-off-by: Jamie Iles <jamie.iles@oracle.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are a few places in the kernel that access stack memory
belonging to a different task. Before we can start freeing task
stacks before the task_struct is freed, we need a way for those code
paths to pin the stack.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jann Horn <jann@thejh.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/17a434f50ad3d77000104f21666575e10a9c1fbd.1474003868.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Bug: 38331309
Change-Id: I414853e9b72ecb0967d5e1cbfc77b4929bf3f4f5
(cherry picked from commit c6c314a613cd7d03fb97713e0d642b493de42e69)
Signed-off-by: Zubin Mithra <zsm@google.com>
If an arch opts in by setting CONFIG_THREAD_INFO_IN_TASK_STRUCT,
then thread_info is defined as a single 'u32 flags' and is the first
entry of task_struct. thread_info::task is removed (it serves no
purpose if thread_info is embedded in task_struct), and
thread_info::cpu gets its own slot in task_struct.
This is heavily based on a patch written by Linus.
Originally-from: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jann Horn <jann@thejh.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a0898196f0476195ca02713691a5037a14f2aac5.1473801993.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Bug: 38331309
Change-Id: I25e5a830f2ada5e74fa93661e97e5e701b1b70d2
(cherry picked from commit c65eacbe290b8141554c71b2c94489e73ade8c8d)
Signed-off-by: Zubin Mithra <zsm@google.com>
We've had the thread info allocated together with the thread stack for
most architectures for a long time (since the thread_info was split off
from the task struct), but that is about to change.
But the patches that move the thread info to be off-stack (and a part of
the task struct instead) made it clear how confused the allocator and
freeing functions are.
Because the common case was that we share an allocation with the thread
stack and the thread_info, the two pointers were identical. That
identity then meant that we would have things like
ti = alloc_thread_info_node(tsk, node);
...
tsk->stack = ti;
which certainly _worked_ (since stack and thread_info have the same
value), but is rather confusing: why are we assigning a thread_info to
the stack? And if we move the thread_info away, the "confusing" code
just gets to be entirely bogus.
So remove all this confusion, and make it clear that we are doing the
stack allocation by renaming and clarifying the function names to be
about the stack. The fact that the thread_info then shares the
allocation is an implementation detail, and not really about the
allocation itself.
This is a pure renaming and type fix: we pass in the same pointer, it's
just that we clarify what the pointer means.
The ia64 code that actually only has one single allocation (for all of
task_struct, thread_info and kernel thread stack) now looks a bit odd,
but since "tsk->stack" is actually not even used there, that oddity
doesn't matter. It would be a separate thing to clean that up, I
intentionally left the ia64 changes as a pure brute-force renaming and
type change.
Acked-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bug: 38331309
Change-Id: I870b5476fc900c9145134f9dd3ed18a32a490162
(cherry picked from commit b235beea9e996a4d36fed6cfef4801a3e7d7a9a5)
Signed-off-by: Zubin Mithra <zsm@google.com>
Add a topology flag to the sched_domain hierarchy indicating the lowest
domain level where the full range of CPU capacities is represented by
the domain members for asymmetric capacity topologies (e.g. ARM
big.LITTLE).
The flag is intended to indicate that extra care should be taken when
placing tasks on CPUs and this level spans all the different types of
CPUs found in the system (no need to look further up the domain
hierarchy). This information is currently only available through
iterating through the capacities of all the CPUs at parent levels in the
sched_domain hierarchy.
SD 2 [ 0 1 2 3] SD_ASYM_CPUCAPACITY
SD 1 [ 0 1] [ 2 3] !SD_ASYM_CPUCAPACITY
CPU: 0 1 2 3
capacity: 756 756 1024 1024
If the topology in the example above is duplicated to create an eight
CPU example with third sched_domain level on top (SD 3), this level
should not have the flag set (!SD_ASYM_CPUCAPACITY) as its two group
would both have all CPU capacities represented within them.
Change-Id: I1526407b90567cac387419719b7d7fdc8b259a85
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: freedom.tan@mediatek.com
Cc: keita.kobayashi.ym@renesas.com
Cc: mgalbraith@suse.de
Cc: sgurrappadi@nvidia.com
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1469453670-2660-6-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 1f6e6c7cb9bcd58abb5ee11243e0eefe6b36fc8e)
[trivial merge conflict]
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
It is seems that this one escaped Nico's renaming of cpu_power to
cpu_capacity a while back.
Change-Id: Ic2569d714db7b740f1df4ccc381ba8c1772c2793
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: linux-kernel@vger.kernel.org
Cc: mgalbraith@suse.de
Cc: vincent.guittot@linaro.org
Cc: yuyang.du@intel.com
Link: http://lkml.kernel.org/r/1466615004-3503-2-git-send-email-morten.rasmussen@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit bd425d4bfc7a1a6064dbbadfbac9c7eec0e426ec)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
A policy of going to fmax on any RT activity will be detrimental
for power on many platforms. Often RT accounts for only a small amount
of CPU activity so sending the CPU frequency to fmax is overkill. Worse
still, some platforms may not be able to even complete the CPU frequency
change before the RT activity has already completed.
Cpufreq governors have not treated RT activity this way in the past so
it is not part of the expected semantics of the RT scheduling class. The
DL class offers guarantees about task completion and could be used for
this purpose.
Modify the schedutil algorithm to instead use rt_avg as an estimate of
RT utilization of the CPU.
Based on previous work by Vincent Guittot <vincent.guittot@linaro.org>.
Change-Id: I1ed605a3e2512a94d34217a8e57c3fd97cca60be
Signed-off-by: Steve Muckle <smuckle@linaro.org>
The scheduler cpufreq hooks are required by the schedutil cpufreq
governor.
Change-Id: Ied6c46262bb33b7e81bbb3d3d2761124e0c676b7
Signed-off-by: Steve Muckle <smuckle@linaro.org>
[trivial cherry-picking fixes]
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
-----BEGIN PGP SIGNATURE-----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=iS0x
-----END PGP SIGNATURE-----
Merge 4.4.63 into android-4.4
Changes in 4.4.63:
cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups
thp: fix MADV_DONTNEED vs clear soft dirty race
drm/nouveau/mpeg: mthd returns true on success now
drm/nouveau/mmu/nv4a: use nv04 mmu rather than the nv44 one
CIFS: store results of cifs_reopen_file to avoid infinite wait
Input: xpad - add support for Razer Wildcat gamepad
perf/x86: Avoid exposing wrong/stale data in intel_pmu_lbr_read_32()
x86/vdso: Ensure vdso32_enabled gets set to valid values only
x86/vdso: Plug race between mapping and ELF header setup
acpi, nfit, libnvdimm: fix interleave set cookie calculation (64-bit comparison)
iscsi-target: Fix TMR reference leak during session shutdown
iscsi-target: Drop work-around for legacy GlobalSAN initiator
scsi: sr: Sanity check returned mode data
scsi: sd: Consider max_xfer_blocks if opt_xfer_blocks is unusable
scsi: sd: Fix capacity calculation with 32-bit sector_t
xen, fbfront: fix connecting to backend
libnvdimm: fix reconfig_mutex, mmap_sem, and jbd2_handle lockdep splat
irqchip/irq-imx-gpcv2: Fix spinlock initialization
ftrace: Fix removing of second function probe
char: Drop bogus dependency of DEVPORT on !M68K
char: lack of bool string made CONFIG_DEVPORT always on
Revert "MIPS: Lantiq: Fix cascaded IRQ setup"
kvm: fix page struct leak in handle_vmon
zram: do not use copy_page with non-page aligned address
powerpc: Disable HFSCR[TM] if TM is not supported
crypto: ahash - Fix EINPROGRESS notification callback
ath9k: fix NULL pointer dereference
dvb-usb-v2: avoid use-after-free
ext4: fix inode checksum calculation problem if i_extra_size is small
platform/x86: acer-wmi: setup accelerometer when machine has appropriate notify event
rtc: tegra: Implement clock handling
mm: Tighten x86 /dev/mem with zeroing reads
dvb-usb: don't use stack for firmware load
dvb-usb-firmware: don't do DMA on stack
virtio-console: avoid DMA from stack
pegasus: Use heap buffers for all register access
rtl8150: Use heap buffers for all register access
catc: Combine failure cleanup code in catc_probe()
catc: Use heap buffer for memory size test
ibmveth: calculate gso_segs for large packets
SUNRPC: fix refcounting problems with auth_gss messages.
tty/serial: atmel: RS485 half duplex w/DMA: enable RX after TX is done
net: ipv6: check route protocol when deleting routes
sctp: deny peeloff operation on asocs with threads sleeping on it
MIPS: fix Select HAVE_IRQ_EXIT_ON_IRQ_STACK patch.
Linux 4.4.63
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 77f88796cee819b9c4562b0b6b44691b3b7755b1 upstream.
Creation of a kthread goes through a couple interlocked stages between
the kthread itself and its creator. Once the new kthread starts
running, it initializes itself and wakes up the creator. The creator
then can further configure the kthread and then let it start doing its
job by waking it up.
In this configuration-by-creator stage, the creator is the only one
that can wake it up but the kthread is visible to userland. When
altering the kthread's attributes from userland is allowed, this is
fine; however, for cases where CPU affinity is critical,
kthread_bind() is used to first disable affinity changes from userland
and then set the affinity. This also prevents the kthread from being
migrated into non-root cgroups as that can affect the CPU affinity and
many other things.
Unfortunately, the cgroup side of protection is racy. While the
PF_NO_SETAFFINITY flag prevents further migrations, userland can win
the race before the creator sets the flag with kthread_bind() and put
the kthread in a non-root cgroup, which can lead to all sorts of
problems including incorrect CPU affinity and starvation.
This bug got triggered by userland which periodically tries to migrate
all processes in the root cpuset cgroup to a non-root one. Per-cpu
workqueue workers got caught while being created and ended up with
incorrected CPU affinity breaking concurrency management and sometimes
stalling workqueue execution.
This patch adds task->no_cgroup_migration which disallows the task to
be migrated by userland. kthreadd starts with the flag set making
every child kthread start in the root cgroup with migration
disallowed. The flag is cleared after the kthread finishes
initialization by which time PF_NO_SETAFFINITY is set if the kthread
should stay in the root cgroup.
It'd be better to wait for the initialization instead of failing but I
couldn't think of a way of implementing that without adding either a
new PF flag, or sleeping and retrying from waiting side. Even if
userland depends on changing cgroup membership of a kthread, it either
has to be synchronized with kthread_create() or periodically repeat,
so it's unlikely that this would break anything.
v2: Switch to a simpler implementation using a new task_struct bit
field suggested by Oleg.
Signed-off-by: Tejun Heo <tj@kernel.org>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reported-and-debugged-by: Chris Mason <clm@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64b875f7ac8a5d60a4e191479299e931ee949b67 upstream.
When the flag PT_PTRACE_CAP was added the PTRACE_TRACEME path was
overlooked. This can result in incorrect behavior when an application
like strace traces an exec of a setuid executable.
Further PT_PTRACE_CAP does not have enough information for making good
security decisions as it does not report which user namespace the
capability is in. This has already allowed one mistake through
insufficient granulariy.
I found this issue when I was testing another corner case of exec and
discovered that I could not get strace to set PT_PTRACE_CAP even when
running strace as root with a full set of caps.
This change fixes the above issue with strace allowing stracing as
root a setuid executable without disabling setuid. More fundamentaly
this change allows what is allowable at all times, by using the correct
information in it's decision.
Fixes: 4214e42f96d4 ("v2.4.9.11 -> v2.4.9.12")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
use a window based view of time in order to track task
demand and CPU utilization in the scheduler.
Window Assisted Load Tracking (WALT) implementation credits:
Srivatsa Vaddagiri, Steve Muckle, Syed Rameez Mustafa, Joonwoo Park,
Pavan Kumar Kondeti, Olav Haugan
2016-03-06: Integration with EAS/refactoring by Vikram Mulukutla
and Todd Kjos
Change-Id: I21408236836625d4e7d7de1843d20ed5ff36c708
Includes fixes for issues:
eas/walt: Use walt_ktime_clock() instead of ktime_get_ns() to avoid a
race resulting in watchdog resets
BUG: 29353986
Change-Id: Ic1820e22a136f7c7ebd6f42e15f14d470f6bbbdb
Handle walt accounting anomoly during resume
During resume, there is a corner case where on wakeup, a task's
prev_runnable_sum can go negative. This is a workaround that
fixes the condition and warns (instead of crashing).
BUG: 29464099
Change-Id: I173e7874324b31a3584435530281708145773508
Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Srinath Sridharan <srinathsr@google.com>
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
[jstultz: fwdported to 4.4]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Doing a Exponential moving average per nr_running++/-- does not
guarantee a fixed sample rate which induces errors if there are lots of
threads being enqueued/dequeued from the rq (Linpack mt). Instead of
keeping track of the avg, the scheduler now keeps track of the integral
of nr_running and allows the readers to perform filtering on top.
Original-author: Sai Charan Gurrappadi <sgurrappadi@nvidia.com>
Change-Id: Id946654f32fa8be0eaf9d8fa7c9a8039b5ef9fab
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/174694
Reviewed-on: https://chromium-review.googlesource.com/272853
[jstultz: fwdported to 4.4]
Signed-off-by: John Stultz <john.stultz@linaro.org>
This backports da8b44d5a9f8bf26da637b7336508ca534d6b319 from upstream.
This patchset introduces a /proc/<pid>/timerslack_ns interface which
would allow controlling processes to be able to set the timerslack value
on other processes in order to save power by avoiding wakeups (Something
Android currently does via out-of-tree patches).
The first patch tries to fix the internal timer_slack_ns usage which was
defined as a long, which limits the slack range to ~4 seconds on 32bit
systems. It converts it to a u64, which provides the same basically
unlimited slack (500 years) on both 32bit and 64bit machines.
The second patch introduces the /proc/<pid>/timerslack_ns interface
which allows the full 64bit slack range for a task to be read or set on
both 32bit and 64bit machines.
With these two patches, on a 32bit machine, after setting the slack on
bash to 10 seconds:
$ time sleep 1
real 0m10.747s
user 0m0.001s
sys 0m0.005s
The first patch is a little ugly, since I had to chase the slack delta
arguments through a number of functions converting them to u64s. Let me
know if it makes sense to break that up more or not.
Other than that things are fairly straightforward.
This patch (of 2):
The timer_slack_ns value in the task struct is currently a unsigned
long. This means that on 32bit applications, the maximum slack is just
over 4 seconds. However, on 64bit machines, its much much larger (~500
years).
This disparity could make application development a little (as well as
the default_slack) to a u64. This means both 32bit and 64bit systems
have the same effective internal slack range.
Now the existing ABI via PR_GET_TIMERSLACK and PR_SET_TIMERSLACK specify
the interface as a unsigned long, so we preserve that limitation on
32bit systems, where SET_TIMERSLACK can only set the slack to a unsigned
long value, and GET_TIMERSLACK will return ULONG_MAX if the slack is
actually larger then what can be stored by an unsigned long.
This patch also modifies hrtimer functions which specified the slack
delta as a unsigned long.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Oren Laadan <orenl@cellrox.com>
Cc: Ruchi Kandoi <kandoiruchi@google.com>
Cc: Rom Lemarchand <romlem@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
commit 759c01142a5d0f364a462346168a56de28a80f52 upstream.
On no-so-small systems, it is possible for a single process to cause an
OOM condition by filling large pipes with data that are never read. A
typical process filling 4000 pipes with 1 MB of data will use 4 GB of
memory. On small systems it may be tricky to set the pipe max size to
prevent this from happening.
This patch makes it possible to enforce a per-user soft limit above
which new pipes will be limited to a single page, effectively limiting
them to 4 kB each, as well as a hard limit above which no new pipes may
be created for this user. This has the effect of protecting the system
against memory abuse without hurting other users, and still allowing
pipes to work correctly though with less data at once.
The limit are controlled by two new sysctls : pipe-user-pages-soft, and
pipe-user-pages-hard. Both may be disabled by setting them to zero. The
default soft limit allows the default number of FDs per process (1024)
to create pipes of the default size (64kB), thus reaching a limit of 64MB
before starting to create only smaller pipes. With 256 processes limited
to 1024 FDs each, this results in 1024*64kB + (256*1024 - 1024) * 4kB =
1084 MB of memory allocated for a user. The hard limit is disabled by
default to avoid breaking existing applications that make intensive use
of pipes (eg: for splicing).
Reported-by: socketpair@gmail.com
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Mitigates: CVE-2013-4312 (Linux 2.0+)
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Moritz Muehlenhoff <moritz@wikimedia.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Scheduler-driven CPU frequency selection hopes to exploit both
per-task and global information in the scheduler to improve frequency
selection policy, achieving lower power consumption, improved
responsiveness/performance, and less reliance on heuristics and
tunables. For further discussion on the motivation of this integration
see [0].
This patch implements a shim layer between the Linux scheduler and the
cpufreq subsystem. The interface accepts capacity requests from the
CFS, RT and deadline sched classes. The requests from each sched class
are summed on each CPU with a margin applied to the CFS and RT
capacity requests to provide some headroom. Deadline requests are
expected to be precise enough given their nature to not require
headroom. The maximum total capacity request for a CPU in a frequency
domain drives the requested frequency for that domain.
Policy is determined by both the sched classes and this shim layer.
Note that this algorithm is event-driven. There is no polling loop to
check cpu idle time nor any other method which is unsynchronized with
the scheduler, aside from a throttling mechanism to ensure frequency
changes are not attempted faster than the hardware can accommodate them.
Thanks to Juri Lelli <juri.lelli@arm.com> for contributing design ideas,
code and test results, and to Ricky Liang <jcliang@chromium.org>
for initialization and static key inc/dec fixes.
[0] http://article.gmane.org/gmane.linux.kernel/1499836
[smuckle@linaro.org: various additions and fixes, revised commit text]
CC: Ricky Liang <jcliang@chromium.org>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Steve Muckle <smuckle@linaro.org>
cpufreq is currently keeping it a secret which cpus are sharing
clock source. The scheduler needs to know about clock domains as well
to become more energy aware. The SD_SHARE_CAP_STATES domain flag
indicates whether cpus belonging to the sched_domain share capacity
states (P-states).
There is no connection with cpufreq (yet). The flag must be set by
the arch specific topology code.
cc: Russell King <linux@arm.linux.org.uk>
cc: Ingo Molnar <mingo@redhat.com>
cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
The struct sched_group_energy represents the per sched_group related
data which is needed for energy aware scheduling. It contains:
(1) number of elements of the idle state array
(2) pointer to the idle state array which comprises 'power consumption'
for each idle state
(3) number of elements of the capacity state array
(4) pointer to the capacity state array which comprises 'compute
capacity and power consumption' tuples for each capacity state
The struct sched_group obtains a pointer to a struct sched_group_energy.
The function pointer sched_domain_energy_f is introduced into struct
sched_domain_topology_level which will allow the arch to pass a particular
struct sched_group_energy from the topology shim layer into the scheduler
core.
The function pointer sched_domain_energy_f has an 'int cpu' parameter
since the folding of two adjacent sd levels via sd degenerate doesn't work
for all sd levels. I.e. it is not possible for example to use this feature
to provide per-cpu energy in sd level DIE on ARM's TC2 platform.
It was discussed that the folding of sd levels approach is preferable
over the cpu parameter approach, simply because the user (the arch
specifying the sd topology table) can introduce less errors. But since
it is not working, the 'int cpu' parameter is the only way out. It's
possible to use the folding of sd levels approach for
sched_domain_flags_f and the cpu parameter approach for the
sched_domain_energy_f at the same time though. With the use of the
'int cpu' parameter, an extra check function has to be provided to make
sure that all cpus spanned by a sched group are provisioned with the same
energy data.
cc: Ingo Molnar <mingo@redhat.com>
cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
[ Upstream commit 712f4aad406bb1ed67f3f98d04c044191f0ff593 ]
It is possible for a process to allocate and accumulate far more FDs than
the process' limit by sending them over a unix socket then closing them
to keep the process' fd count low.
This change addresses this problem by keeping track of the number of FDs
in flight per user and preventing non-privileged processes from having
more FDs in flight than their configured FD limit.
Reported-by: socketpair@gmail.com
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Mitigates: CVE-2013-4312 (Linux 2.0+)
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some of the sched bitfieds (notably sched_reset_on_fork) can be set
on other than current, this can cause the r-m-w to race with other
updates.
Since all the sched bits are serialized by scheduler locks, pull them
in a separate word.
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: hannes@cmpxchg.org
Cc: mhocko@kernel.org
Cc: vdavydov@parallels.com
Link: http://lkml.kernel.org/r/20151125150207.GM11639@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Our global init task can have sub-threads, so ->pid check is not reliable
enough for is_global_init(), we need to check tgid instead. This has been
spotted by Oleg and a fix was proposed by Richard a long time ago (see the
link below).
Oleg wrote:
: Because is_global_init() is only true for the main thread of /sbin/init.
:
: Just look at oom_unkillable_task(). It tries to not kill init. But, say,
: select_bad_process() can happily find a sub-thread of is_global_init()
: and still kill it.
I recently hit the problem in question; re-sending the patch (to the
best of my knowledge it has never been submitted) with updated function
comment. Credit goes to Oleg and Richard.
Suggested-by: Richard Guy Briggs <rgb@redhat.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W . Biederman <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge E . Hallyn <serge.hallyn@ubuntu.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://www.redhat.com/archives/linux-audit/2013-December/msg00086.html
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1/ Add support for the ACPI 6.0 NFIT hot add mechanism to process
updates of the NFIT at runtime.
2/ Teach the coredump implementation how to filter out DAX mappings.
3/ Introduce NUMA hints for allocations made by the pmem driver, and as
a side effect all devm allocations now hint their NUMA node by
default.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=a2/L
-----END PGP SIGNATURE-----
Merge tag 'libnvdimm-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"Outside of the new ACPI-NFIT hot-add support this pull request is more
notable for what it does not contain, than what it does. There were a
handful of development topics this cycle, dax get_user_pages, dax
fsync, and raw block dax, that need more more iteration and will wait
for 4.5.
The patches to make devm and the pmem driver NUMA aware have been in
-next for several weeks. The hot-add support has not, but is
contained to the NFIT driver and is passing unit tests. The coredump
support is straightforward and was looked over by Jeff. All of it has
received a 0day build success notification across 107 configs.
Summary:
- Add support for the ACPI 6.0 NFIT hot add mechanism to process
updates of the NFIT at runtime.
- Teach the coredump implementation how to filter out DAX mappings.
- Introduce NUMA hints for allocations made by the pmem driver, and
as a side effect all devm allocations now hint their NUMA node by
default"
* tag 'libnvdimm-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
coredump: add DAX filtering for FDPIC ELF coredumps
coredump: add DAX filtering for ELF coredumps
acpi: nfit: Add support for hot-add
nfit: in acpi_nfit_init, break on a 0-length table
pmem, memremap: convert to numa aware allocations
devm_memremap_pages: use numa_mem_id
devm: make allocations numa aware by default
devm_memremap: convert to return ERR_PTR
devm_memunmap: use devres_release()
pmem: kill memremap_pmem()
x86, mm: quiet arch_add_memory()
Add two new flags to the existing coredump mechanism for ELF files to
allow us to explicitly filter DAX mappings. This is desirable because
DAX mappings, like hugetlb mappings, have the potential to be very
large.
Update the coredump_filter documentation in
Documentation/filesystems/proc.txt so that it addresses the new DAX
coredump flags. Also update the documented default value of
coredump_filter to be consistent with the core(5) man page. The
documentation being updated talks about bit 4, Dump ELF headers, which
is enabled if CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS is turned on in the
kernel config. This kernel config option defaults to "y" if both ELF
binaries and coredump are enabled.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
jffs2_garbage_collect_thread() can race with SIGCONT and sleep in
TASK_STOPPED state after it was already sent. Add the new helper,
kernel_signal_stop(), which does this correctly.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1. Rename dequeue_signal_lock() to kernel_dequeue_signal(). This
matches another "for kthreads only" kernel_sigaction() helper.
2. Remove the "tsk" and "mask" arguments, they are always current
and current->blocked. And it is simply wrong if tsk != current.
3. We could also remove the 3rd "siginfo_t *info" arg but it looks
potentially useful. However we can simplify the callers if we
change kernel_dequeue_signal() to accept info => NULL.
4. Remove _irqsave, it is never called from atomic context.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
