Commit graph

597974 commits

Author SHA1 Message Date
KarimAllah Ahmed
3fc9b05df6 x86/spectre: Simplify spectre_v2 command line parsing
(cherry picked from commit 9005c6834c0ffdfe46afa76656bd9276cca864f6)

[dwmw2: Use ARRAY_SIZE]

Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Cc: bp@alien8.de
Link: https://lkml.kernel.org/r/1517484441-1420-3-git-send-email-dwmw@amazon.co.uk
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:54 +01:00
David Woodhouse
b98197294b x86/retpoline: Avoid retpolines for built-in __init functions
(cherry picked from commit 66f793099a636862a71c59d4a6ba91387b155e0c)

There's no point in building init code with retpolines, since it runs before
any potentially hostile userspace does. And before the retpoline is actually
ALTERNATIVEd into place, for much of it.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: karahmed@amazon.de
Cc: peterz@infradead.org
Cc: bp@alien8.de
Link: https://lkml.kernel.org/r/1517484441-1420-2-git-send-email-dwmw@amazon.co.uk
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: port to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:54 +01:00
Dan Williams
355e059499 x86/kvm: Update spectre-v1 mitigation
(cherry picked from commit 085331dfc6bbe3501fb936e657331ca943827600)

Commit 75f139aaf896 "KVM: x86: Add memory barrier on vmcs field lookup"
added a raw 'asm("lfence");' to prevent a bounds check bypass of
'vmcs_field_to_offset_table'.

The lfence can be avoided in this path by using the array_index_nospec()
helper designed for these types of fixes.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andrew Honig <ahonig@google.com>
Cc: kvm@vger.kernel.org
Cc: Jim Mattson <jmattson@google.com>
Link: https://lkml.kernel.org/r/151744959670.6342.3001723920950249067.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:54 +01:00
Josh Poimboeuf
ac0242fe0d x86/paravirt: Remove 'noreplace-paravirt' cmdline option
(cherry picked from commit 12c69f1e94c89d40696e83804dd2f0965b5250cd)

The 'noreplace-paravirt' option disables paravirt patching, leaving the
original pv indirect calls in place.

That's highly incompatible with retpolines, unless we want to uglify
paravirt even further and convert the paravirt calls to retpolines.

As far as I can tell, the option doesn't seem to be useful for much
other than introducing surprising corner cases and making the kernel
vulnerable to Spectre v2.  It was probably a debug option from the early
paravirt days.  So just remove it.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: https://lkml.kernel.org/r/20180131041333.2x6blhxirc2kclrq@treble
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: chery pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:54 +01:00
Colin Ian King
bf17809d19 x86/spectre: Fix spelling mistake: "vunerable"-> "vulnerable"
(cherry picked from commit e698dcdfcda41efd0984de539767b4cddd235f1e)

Trivial fix to spelling mistake in pr_err error message text.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: kernel-janitors@vger.kernel.org
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lkml.kernel.org/r/20180130193218.9271-1-colin.king@canonical.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:54 +01:00
Dan Williams
b9c288b664 x86/spectre: Report get_user mitigation for spectre_v1
(cherry picked from commit edfbae53dab8348fca778531be9f4855d2ca0360)

Reflect the presence of get_user(), __get_user(), and 'syscall' protections
in sysfs. The expectation is that new and better tooling will allow the
kernel to grow more usages of array_index_nospec(), for now, only claim
mitigation for __user pointer de-references.

Reported-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727420158.33451.11658324346540434635.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Dan Williams
f7b9243f5f nl80211: Sanitize array index in parse_txq_params
(cherry picked from commit 259d8c1e984318497c84eef547bbb6b1d9f4eb05)

Wireless drivers rely on parse_txq_params to validate that txq_params->ac
is less than NL80211_NUM_ACS by the time the low-level driver's ->conf_tx()
handler is called. Use a new helper, array_index_nospec(), to sanitize
txq_params->ac with respect to speculation. I.e. ensure that any
speculation into ->conf_tx() handlers is done with a value of
txq_params->ac that is within the bounds of [0, NL80211_NUM_ACS).

Reported-by: Christian Lamparter <chunkeey@gmail.com>
Reported-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: linux-wireless@vger.kernel.org
Cc: torvalds@linux-foundation.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727419584.33451.7700736761686184303.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Dan Williams
43e4f5aeaf vfs, fdtable: Prevent bounds-check bypass via speculative execution
(cherry picked from commit 56c30ba7b348b90484969054d561f711ba196507)

'fd' is a user controlled value that is used as a data dependency to
read from the 'fdt->fd' array.  In order to avoid potential leaks of
kernel memory values, block speculative execution of the instruction
stream that could issue reads based on an invalid 'file *' returned from
__fcheck_files.

Co-developed-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727418500.33451.17392199002892248656.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Dan Williams
c8961332d6 x86/syscall: Sanitize syscall table de-references under speculation
(cherry picked from commit 2fbd7af5af8665d18bcefae3e9700be07e22b681)

The syscall table base is a user controlled function pointer in kernel
space. Use array_index_nospec() to prevent any out of bounds speculation.

While retpoline prevents speculating into a userspace directed target it
does not stop the pointer de-reference, the concern is leaking memory
relative to the syscall table base, by observing instruction cache
behavior.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Andy Lutomirski <luto@kernel.org>
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727417984.33451.1216731042505722161.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: port to 4.4, no syscall_64]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Dan Williams
fd3d953545 x86/get_user: Use pointer masking to limit speculation
(cherry picked from commit c7f631cb07e7da06ac1d231ca178452339e32a94)

Quoting Linus:

    I do think that it would be a good idea to very expressly document
    the fact that it's not that the user access itself is unsafe. I do
    agree that things like "get_user()" want to be protected, but not
    because of any direct bugs or problems with get_user() and friends,
    but simply because get_user() is an excellent source of a pointer
    that is obviously controlled from a potentially attacking user
    space. So it's a prime candidate for then finding _subsequent_
    accesses that can then be used to perturb the cache.

Unlike the __get_user() case get_user() includes the address limit check
near the pointer de-reference. With that locality the speculation can be
mitigated with pointer narrowing rather than a barrier, i.e.
array_index_nospec(). Where the narrowing is performed by:

	cmp %limit, %ptr
	sbb %mask, %mask
	and %mask, %ptr

With respect to speculation the value of %ptr is either less than %limit
or NULL.

Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727417469.33451.11804043010080838495.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: port to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Dan Williams
64d41d13ed x86: Introduce barrier_nospec
(cherry picked from commit b3d7ad85b80bbc404635dca80f5b129f6242bc7a)

Rename the open coded form of this instruction sequence from
rdtsc_ordered() into a generic barrier primitive, barrier_nospec().

One of the mitigations for Spectre variant1 vulnerabilities is to fence
speculative execution after successfully validating a bounds check. I.e.
force the result of a bounds check to resolve in the instruction pipeline
to ensure speculative execution honors that result before potentially
operating on out-of-bounds data.

No functional changes.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Andi Kleen <ak@linux.intel.com>
Suggested-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727415361.33451.9049453007262764675.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Dan Williams
f136b56017 x86: Implement array_index_mask_nospec
(cherry picked from commit babdde2698d482b6c0de1eab4f697cf5856c5859)

array_index_nospec() uses a mask to sanitize user controllable array
indexes, i.e. generate a 0 mask if 'index' >= 'size', and a ~0 mask
otherwise. While the default array_index_mask_nospec() handles the
carry-bit from the (index - size) result in software.

The x86 array_index_mask_nospec() does the same, but the carry-bit is
handled in the processor CF flag without conditional instructions in the
control flow.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727414808.33451.1873237130672785331.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang:chery pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Dan Williams
37b33b59ec array_index_nospec: Sanitize speculative array de-references
(cherry picked from commit f3804203306e098dae9ca51540fcd5eb700d7f40)

array_index_nospec() is proposed as a generic mechanism to mitigate
against Spectre-variant-1 attacks, i.e. an attack that bypasses boundary
checks via speculative execution. The array_index_nospec()
implementation is expected to be safe for current generation CPUs across
multiple architectures (ARM, x86).

Based on an original implementation by Linus Torvalds, tweaked to remove
speculative flows by Alexei Starovoitov, and tweaked again by Linus to
introduce an x86 assembly implementation for the mask generation.

Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Co-developed-by: Alexei Starovoitov <ast@kernel.org>
Suggested-by: Cyril Novikov <cnovikov@lynx.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727414229.33451.18411580953862676575.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Mark Rutland
3416cebfd1 Documentation: Document array_index_nospec
(cherry picked from commit f84a56f73dddaeac1dba8045b007f742f61cd2da)

Document the rationale and usage of the new array_index_nospec() helper.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: linux-arch@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: kernel-hardening@lists.openwall.com
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727413645.33451.15878817161436755393.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Dou Liyang
131f3e8866 x86/spectre: Check CONFIG_RETPOLINE in command line parser
(cherry picked from commit 9471eee9186a46893726e22ebb54cade3f9bc043)

The spectre_v2 option 'auto' does not check whether CONFIG_RETPOLINE is
enabled. As a consequence it fails to emit the appropriate warning and sets
feature flags which have no effect at all.

Add the missing IS_ENABLED() check.

Fixes: da285121560e ("x86/spectre: Add boot time option to select Spectre v2 mitigation")
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: Tomohiro <misono.tomohiro@jp.fujitsu.com>
Cc: dave.hansen@intel.com
Cc: bp@alien8.de
Cc: arjan@linux.intel.com
Cc: dwmw@amazon.co.uk
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/f5892721-7528-3647-08fb-f8d10e65ad87@cn.fujitsu.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry-pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:53 +01:00
Thomas Gleixner
e905005d58 x86/cpu/bugs: Make retpoline module warning conditional
(cherry picked from commit e383095c7fe8d218e00ec0f83e4b95ed4e627b02)

If sysfs is disabled and RETPOLINE not defined:

arch/x86/kernel/cpu/bugs.c:97:13: warning: ‘spectre_v2_bad_module’ defined but not used
[-Wunused-variable]
 static bool spectre_v2_bad_module;

Hide it.

Fixes: caf7501a1b4e ("module/retpoline: Warn about missing retpoline in module")
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: port to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Borislav Petkov
e9560fbe97 x86/bugs: Drop one "mitigation" from dmesg
(cherry picked from commit 55fa19d3e51f33d9cd4056d25836d93abf9438db)

Make

[    0.031118] Spectre V2 mitigation: Mitigation: Full generic retpoline

into

[    0.031118] Spectre V2: Mitigation: Full generic retpoline

to reduce the mitigation mitigations strings.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: riel@redhat.com
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: jikos@kernel.org
Cc: luto@amacapital.net
Cc: dave.hansen@intel.com
Cc: torvalds@linux-foundation.org
Cc: keescook@google.com
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: tim.c.chen@linux.intel.com
Cc: pjt@google.com
Link: https://lkml.kernel.org/r/20180126121139.31959-5-bp@alien8.de
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: port to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Borislav Petkov
3d535a0f55 x86/nospec: Fix header guards names
(cherry picked from commit 7a32fc51ca938e67974cbb9db31e1a43f98345a9)

... to adhere to the _ASM_X86_ naming scheme.

No functional change.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: riel@redhat.com
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: jikos@kernel.org
Cc: luto@amacapital.net
Cc: dave.hansen@intel.com
Cc: torvalds@linux-foundation.org
Cc: keescook@google.com
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Cc: pjt@google.com
Link: https://lkml.kernel.org/r/20180126121139.31959-3-bp@alien8.de
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[cherry-pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Andi Kleen
6cd5513c81 module/retpoline: Warn about missing retpoline in module
(cherry picked from commit caf7501a1b4ec964190f31f9c3f163de252273b8)

There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.

To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.

If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.

[ tglx: Massaged changelog ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: port to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Peter Zijlstra
d5030418b0 KVM: VMX: Make indirect call speculation safe
(cherry picked from commit c940a3fb1e2e9b7d03228ab28f375fb5a47ff699)

Replace indirect call with CALL_NOSPEC.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: rga@amazon.de
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lkml.kernel.org/r/20180125095843.645776917@infradead.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[backport to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Peter Zijlstra
5dac465887 KVM: x86: Make indirect calls in emulator speculation safe
(cherry picked from commit 1a29b5b7f347a1a9230c1e0af5b37e3e571588ab)

Replace the indirect calls with CALL_NOSPEC.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: rga@amazon.de
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lkml.kernel.org/r/20180125095843.595615683@infradead.org
[dwmw2: Use ASM_CALL_CONSTRAINT like upstream, now we have it]
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[backport to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Waiman Long
ffe69f2dd1 x86/retpoline: Remove the esp/rsp thunk
commit 1df37383a8aeabb9b418698f0bcdffea01f4b1b2 upstream.

It doesn't make sense to have an indirect call thunk with esp/rsp as
retpoline code won't work correctly with the stack pointer register.
Removing it will help compiler writers to catch error in case such
a thunk call is emitted incorrectly.

Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support")
Suggested-by: Jeff Law <law@redhat.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Kees Cook <keescook@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1516658974-27852-1-git-send-email-longman@redhat.com
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: cherry pick to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Wanpeng Li
5f75371332 KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously
commit 9a6e7c39810e4a8bc7fc95056cefb40583fe07ef upstream.

qemu-system-x86-8600  [004] d..1  7205.687530: kvm_entry: vcpu 2
qemu-system-x86-8600  [004] ....  7205.687532: kvm_exit: reason EXCEPTION_NMI rip 0xffffffffa921297d info ffffeb2c0e44e018 80000b0e
qemu-system-x86-8600  [004] ....  7205.687532: kvm_page_fault: address ffffeb2c0e44e018 error_code 0
qemu-system-x86-8600  [004] ....  7205.687620: kvm_try_async_get_page: gva = 0xffffeb2c0e44e018, gfn = 0x427e4e
qemu-system-x86-8600  [004] .N..  7205.687628: kvm_async_pf_not_present: token 0x8b002 gva 0xffffeb2c0e44e018
    kworker/4:2-7814  [004] ....  7205.687655: kvm_async_pf_completed: gva 0xffffeb2c0e44e018 address 0x7fcc30c4e000
qemu-system-x86-8600  [004] ....  7205.687703: kvm_async_pf_ready: token 0x8b002 gva 0xffffeb2c0e44e018
qemu-system-x86-8600  [004] d..1  7205.687711: kvm_entry: vcpu 2

After running some memory intensive workload in guest, I catch the kworker
which completes the GUP too quickly, and queues an "Page Ready" #PF exception
after the "Page not Present" exception before the next vmentry as the above
trace which will result in #DF injected to guest.

This patch fixes it by clearing the queue for "Page not Present" if "Page Ready"
occurs before the next vmentry since the GUP has already got the required page
and shadow page table has already been fixed by "Page Ready" handler.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Fixes: 7c90705bf2 ("KVM: Inject asynchronous page fault into a PV guest if page is swapped out.")
[Changed indentation and added clearing of injected. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[port from upstream v4.14-rc1, Don't assign to kvm_queued_exception::injected or
 x86_exception::async_page_fault]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Arnd Bergmann
0ffa39fb59 kasan: rework Kconfig settings
commit e7c52b84fb18f08ce49b6067ae6285aca79084a8 upstream.

We get a lot of very large stack frames using gcc-7.0.1 with the default
-fsanitize-address-use-after-scope --param asan-stack=1 options, which can
easily cause an overflow of the kernel stack, e.g.

  drivers/gpu/drm/i915/gvt/handlers.c:2434:1: warning: the frame size of 46176 bytes is larger than 3072 bytes
  drivers/net/wireless/ralink/rt2x00/rt2800lib.c:5650:1: warning: the frame size of 23632 bytes is larger than 3072 bytes
  lib/atomic64_test.c:250:1: warning: the frame size of 11200 bytes is larger than 3072 bytes
  drivers/gpu/drm/i915/gvt/handlers.c:2621:1: warning: the frame size of 9208 bytes is larger than 3072 bytes
  drivers/media/dvb-frontends/stv090x.c:3431:1: warning: the frame size of 6816 bytes is larger than 3072 bytes
  fs/fscache/stats.c:287:1: warning: the frame size of 6536 bytes is larger than 3072 bytes

To reduce this risk, -fsanitize-address-use-after-scope is now split out
into a separate CONFIG_KASAN_EXTRA Kconfig option, leading to stack
frames that are smaller than 2 kilobytes most of the time on x86_64.  An
earlier version of this patch also prevented combining KASAN_EXTRA with
KASAN_INLINE, but that is no longer necessary with gcc-7.0.1.

All patches to get the frame size below 2048 bytes with CONFIG_KASAN=y
and CONFIG_KASAN_EXTRA=n have been merged by maintainers now, so we can
bring back that default now.  KASAN_EXTRA=y still causes lots of
warnings but now defaults to !COMPILE_TEST to disable it in
allmodconfig, and it remains disabled in all other defconfigs since it
is a new option.  I arbitrarily raise the warning limit for KASAN_EXTRA
to 3072 to reduce the noise, but an allmodconfig kernel still has around
50 warnings on gcc-7.

I experimented a bit more with smaller stack frames and have another
follow-up series that reduces the warning limit for 64-bit architectures
to 1280 bytes (without CONFIG_KASAN).

With earlier versions of this patch series, I also had patches to address
the warnings we get with KASAN and/or KASAN_EXTRA, using a
"noinline_if_stackbloat" annotation.

That annotation now got replaced with a gcc-8 bugfix (see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715) and a workaround for
older compilers, which means that KASAN_EXTRA is now just as bad as
before and will lead to an instant stack overflow in a few extreme
cases.

This reverts parts of commit 3f181b4d86 ("lib/Kconfig.debug: disable
-Wframe-larger-than warnings with KASAN=y").  Two patches in linux-next
should be merged first to avoid introducing warnings in an allmodconfig
build:
  3cd890dbe2a4 ("media: dvb-frontends: fix i2c access helpers for KASAN")
  16c3ada89cff ("media: r820t: fix r820t_write_reg for KASAN")

Do we really need to backport this?

I think we do: without this patch, enabling KASAN will lead to
unavoidable kernel stack overflow in certain device drivers when built
with gcc-7 or higher on linux-4.10+ or any version that contains a
backport of commit c5caf21ab0cf8.  Most people are probably still on
older compilers, but it will get worse over time as they upgrade their
distros.

The warnings we get on kernels older than this should all be for code
that uses dangerously large stack frames, though most of them do not
cause an actual stack overflow by themselves.The asan-stack option was
added in linux-4.0, and commit 3f181b4d86 ("lib/Kconfig.debug:
disable -Wframe-larger-than warnings with KASAN=y") effectively turned
off the warning for allmodconfig kernels, so I would like to see this
fix backported to any kernels later than 4.0.

I have done dozens of fixes for individual functions with stack frames
larger than 2048 bytes with asan-stack, and I plan to make sure that
all those fixes make it into the stable kernels as well (most are
already there).

Part of the complication here is that asan-stack (from 4.0) was
originally assumed to always require much larger stacks, but that
turned out to be a combination of multiple gcc bugs that we have now
worked around and fixed, but sanitize-address-use-after-scope (from
v4.10) has a much higher inherent stack usage and also suffers from at
least three other problems that we have analyzed but not yet fixed
upstream, each of them makes the stack usage more severe than it should
be.

Link: http://lkml.kernel.org/r/20171221134744.2295529-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[arnd: rebase to v4.4; only re-enable warning]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Sudip Mukherjee
f45cd9bda5 drm/gma500: remove helper function
commit db9b60400f9253c25ae639797df2d0ff7a35d9d8 upstream.

We were getting build warning about:
drivers/gpu/drm/gma500/mdfld_dsi_output.c:407:2: warning: initialization
	from incompatible pointer type

The callback to dpms was pointing to a helper function which had a
return type of void, whereas the callback should point to a function
which has a return type of int.
On closer look it turned out that we do not need the helper function
since if we call drm_helper_connector_dpms() directly, the first check
that drm_helper_connector_dpms() does is: if (mode == connector->dpms)

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1454393155-13142-1-git-send-email-sudipm.mukherjee@gmail.com
Acked-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
[arnd: rebased to 4.4]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:52 +01:00
Borislav Petkov
26c3a6a7f5 x86/microcode/AMD: Change load_microcode_amd()'s param to bool to fix preemptibility bug
commit dac6ca243c4c49a9ca7507d3d66140ebfac8b04b upstream.

With CONFIG_DEBUG_PREEMPT enabled, I get:

  BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
  caller is debug_smp_processor_id
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.12.0-rc2+ #2
  Call Trace:
   dump_stack
   check_preemption_disabled
   debug_smp_processor_id
   save_microcode_in_initrd_amd
   ? microcode_init
   save_microcode_in_initrd
   ...

because, well, it says it above, we're using smp_processor_id() in
preemptible code.

But passing the CPU number is not really needed. It is only used to
determine whether we're on the BSP, and, if so, to save the microcode
patch for early loading.

 [ We don't absolutely need to do it on the BSP but we do that
   customarily there. ]

Instead, convert that function parameter to a boolean which denotes
whether the patch should be saved or not, thereby avoiding the use of
smp_processor_id() in preemptible code.

Signed-off-by: Borislav Petkov <bp@suse.de>
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/20170528200414.31305-1-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[arnd: rebased to 4.9, after running into warning:
 arch/x86/kernel/cpu/microcode/amd.c:881:30: self-comparison always evaluates to true]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Michal Marek
d93cf73400 genksyms: Fix segfault with invalid declarations
commit d920f7c6628c63a390009c237fb80a203c2e400a upstream.

Do not try to recover too early and segfault when parsing invalid
declarations such as

echo 'int (int);' | scripts/genksyms/genksyms
echo 'int a, (int);' | scripts/genksyms/genksyms
echo 'extern void *__inline_memcpy((void *), (const void *), (__kernel_size_t));' | scripts/genksyms/genksyms

The last one was a real-life bug with
include/asm-generic/asm-prototypes.h on x86_64.

Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
[arnd: rebase to 4.4, regenerate parse.tab.{c,h}]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Andy Lutomirski
5381db24f6 dell-wmi, dell-laptop: depends DMI
commit a570af4850043260b87fb1b8aa27a4484e648878 upstream.

dell-wmi and dell-laptop will compile but won't work right if DMI
isn't selected.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Pali Rohár <pali.rohar@gmail.com>
[arnd: Use depends instead of selects to avoid recursive dependencies]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
[arnd: rebase to 4.4-stable]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Arnd Bergmann
15a242fd43 netlink: fix nla_put_{u8,u16,u32} for KASAN
commit b4391db42308c9940944b5d7be5ca4b78fb88dd0 upstream.

When CONFIG_KASAN is enabled, the "--param asan-stack=1" causes rather large
stack frames in some functions. This goes unnoticed normally because
CONFIG_FRAME_WARN is disabled with CONFIG_KASAN by default as of commit
3f181b4d86 ("lib/Kconfig.debug: disable -Wframe-larger-than warnings with
KASAN=y").

The kernelci.org build bot however has the warning enabled and that led
me to investigate it a little further, as every build produces these warnings:

net/wireless/nl80211.c:4389:1: warning: the frame size of 2240 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/wireless/nl80211.c:1895:1: warning: the frame size of 3776 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/wireless/nl80211.c:1410:1: warning: the frame size of 2208 bytes is larger than 2048 bytes [-Wframe-larger-than=]
net/bridge/br_netlink.c:1282:1: warning: the frame size of 2544 bytes is larger than 2048 bytes [-Wframe-larger-than=]

Most of this problem is now solved in gcc-8, which can consolidate
the stack slots for the inline function arguments. On older compilers
we can add a workaround by declaring a local variable in each function
to pass the inline function argument.

Cc: stable@vger.kernel.org
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
[arnd: rebased to 4.4-stable]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Vinod Koul
bd84055a37 ASoC: Intel: Kconfig: fix build when ACPI is not enabled
commit 3493d4a86457c7de9f1e602b4267c9b0f9ec1c9f upstream.

Randy reported following error when ACPI is not enabled:

warning: (SND_SOC_INTEL_BYTCR_RT5640_MACH && SND_SOC_INTEL_BYTCR_RT5651_MACH
&& SND_SOC_INTEL_CHT_BSW_RT5672_MACH && SND_SOC_INTEL_CHT_BSW_RT5645_MACH &&
SND_SOC_INTEL_CHT_BSW_MAX98090_TI_MACH) selects SND_SST_IPC_ACPI
+which has unmet direct dependencies (SOUND && !M68K && !UML && SND &&
SND_SOC && ACPI)

causing these build errors:

In file included from ../sound/soc/intel/atom/sst/sst_acpi.c:40:0:
../include/acpi/acpi_bus.h:65:20: error: conflicting types for
'acpi_evaluate_dsm'
 union acpi_object *acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid,
In file included from ../sound/soc/intel/atom/sst/sst_acpi.c:31:0:
../include/linux/acpi.h:676:34: note: previous definition of
'acpi_evaluate_dsm' was here
 static inline union acpi_object *acpi_evaluate_dsm(acpi_handle handle,

CONFIG_SND_SST_IPC_ACPI was already dependent upon ACPI, but that was not
solving it. So move the depends up to machine drivers and remove from
CONFIG_SND_SST_IPC_ACPI.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
[arnd: rebased to PATCH kernel]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Arnd Bergmann
0522f5e8c0 ARM: tegra: select USB_ULPI from EHCI rather than platform
commit a262e87ff354f12447bb6268bd63edf7ba1c20e0 upstream.

For historic reasons, the tegra platform selects USB_ULPI from architecture
code, but that hasn't really made sense for a long time, as the only
user of that code is the Tegra EHCI driver that has its own Kconfig
symbol.

This removes the 'select' statements from mach-tegra and drivers/soc/tegra
and adds them with the device driver that actually needs them.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
[arnd: rebased to 4.4-stable]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Arnd Bergmann
4d48916f27 ncr5380: shut up gcc indentation warning
gcc-6 and higher warn about the way some loops are written in
the ncr5380 driver:

drivers/scsi/g_NCR5380.c: In function 'generic_NCR5380_pread':
drivers/scsi/g_NCR5380.c:541:3: error: this 'while' clause does not guard... [-Werror=misleading-indentation]
   while (NCR5380_read(C400_CONTROL_STATUS_REG) & CSR_HOST_BUF_NOT_RDY);
   ^~~~~
drivers/scsi/g_NCR5380.c:544:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'while'

This was addressed in mainline kernels as part of a rework on commit
12150797d064 ("ncr5380: Use runtime register mapping"). We don't
want the entire patch backported to stable kernels, but we can
backport one hunk to get rid of the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Arnd Bergmann
18e5cdf6f4 usb: phy: msm add regulator dependency
On linux-4.4 and linux-4.9 we get a warning about an array that is
never initialized when CONFIG_REGULATOR is disabled:

drivers/usb/phy/phy-msm-usb.c: In function 'msm_otg_probe':
drivers/usb/phy/phy-msm-usb.c:1911:14: error: 'regs[0].consumer' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  motg->vddcx = regs[0].consumer;
  ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
drivers/usb/phy/phy-msm-usb.c:1912:14: error: 'regs[1].consumer' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  motg->v3p3  = regs[1].consumer;
  ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
drivers/usb/phy/phy-msm-usb.c:1913:14: error: 'regs[2].consumer' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  motg->v1p8  = regs[2].consumer;

This adds a Kconfig dependency for it. In newer kernels, the driver no
longer exists, so this is only needed for stable kernels.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Arnd Bergmann
3596e409a4 idle: i7300: add PCI dependency
GCC correctly points out an uninitialized variable use when CONFIG_PCI is disabled.

drivers/idle/i7300_idle.c: In function 'i7300_idle_notifier':
include/asm-generic/bug.h:119:5: error: 'got_ctl' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  if (unlikely(__ret_warn_once && !__warned)) {  \
     ^
drivers/idle/i7300_idle.c:415:5: note: 'got_ctl' was declared here
  u8 got_ctl;
     ^~~~~~~

The driver no longer exists in later kernels, so this patch only appplies to
linux-4.9.y and earlier.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Arnd Bergmann
b8b624d988 binfmt_elf: compat: avoid unused function warning
When CONFIG_ELF_CORE is disabled, we get a harmless warning in the compat
version of binfmt_elf:

fs/compat_binfmt_elf.c:58:13: error: 'cputime_to_compat_timeval' defined but not used [-Werror=unused-function]

This was addressed in mainline Linux as part of a larger rework with commit
cd19c364b313 ("fs/binfmt: Convert obsolete cputime type to nsecs").

For 4.9 and earlier, this just shuts up the warning by adding an #ifdef
around the function definition.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Arnd Bergmann
9e9c3045bb isdn: sc: work around type mismatch warning
This driver shows warnings on many architectures:

drivers/isdn/sc/init.c: In function 'identify_board':
drivers/isdn/sc/init.c:484:2: error: passing argument 1 of 'readl' makes pointer from integer without a cast [-Werror]

In newer kernels, it was completely removed, but for the 4.4-stable
series, let's just shut up that warning by adding an extra variable
to do the necessary type cast.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:51 +01:00
Arnd Bergmann
e8988dbe21 power: bq27xxx_battery: mark some symbols __maybe_unused
Without the I2C driver, we get a few warnings:

drivers/power/bq27xxx_battery.c:288:12: error: 'bq27xxx_regs' defined but not used [-Werror=unused-variable]
 static u8 *bq27xxx_regs[] = {
            ^
drivers/power/bq27xxx_battery.c:994:12: error: 'bq27xxx_powersupply_init' defined but not used [-Werror=unused-function]
 static int bq27xxx_powersupply_init(struct bq27xxx_device_info *di,
            ^
drivers/power/bq27xxx_battery.c:1029:13: error: 'bq27xxx_powersupply_unregister' defined but not used [-Werror=unused-function]
 static void bq27xxx_powersupply_unregister(struct bq27xxx_device_info *di)
             ^

In mainline kernels, this was addressed by a larger rework in 703df6c09795 ("power:
bq27xxx_battery: Reorganize I2C into a module"). We probably don't want this backported
into stable kernels, so instead let's shut up the warnings by marking the symbols
as __maybe_unused.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Arnd Bergmann
7131acefb9 Revert "power: bq27xxx_battery: Remove unneeded dependency in Kconfig"
This reverts commit 6bd03ce3c1, it was applied
in error and cuased this link failure

drivers/built-in.o: In function `bq27xxx_battery_i2c_read':
core.c:(.text+0xa6da8): undefined reference to `i2c_transfer'
drivers/built-in.o: In function `bq27xxx_battery_init':
core.c:(.init.text+0x68e0): undefined reference to `i2c_register_driver'
drivers/built-in.o: In function `bq27xxx_battery_exit':
core.c:(.exit.text+0xc6c): undefined reference to `i2c_del_driver'

Later upstream kernels fixed this with a larger rework in commit
703df6c09795 ("power: bq27xxx_battery: Reorganize I2C into a module"),
but we cannot backport that to 4.4.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Miklos Szeredi
633c324b82 ncpfs: fix unused variable warning
commit 9a232de4999666b2e8ea6775b2b0e3e4feb09b7a upstream.

Without CONFIG_NCPFS_NLS the following warning is seen:

fs/ncpfs/dir.c: In function 'ncp_hash_dentry':
fs/ncpfs/dir.c:136:23: warning: unused variable 'sb' [-Wunused-variable]
   struct super_block *sb = dentry->d_sb;

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Arnd Bergmann
ac331bd2f6 gpio: xgene: mark PM functions as __maybe_unused
commit b115bebc07f282067eccc06fd5aa3060ab1426da upstream.

When CONFIG_PM_SLEEP is disabled, we get a warning about unused functions:

drivers/gpio/gpio-xgene.c:155:12: warning: 'xgene_gpio_resume' defined but not used [-Wunused-function]
 static int xgene_gpio_resume(struct device *dev)
            ^~~~~~~~~~~~~~~~~
drivers/gpio/gpio-xgene.c:142:12: warning: 'xgene_gpio_suspend' defined but not used [-Wunused-function]
 static int xgene_gpio_suspend(struct device *dev)

The warnings are harmless and can be avoided by simplifying the code and marking
the functions as __maybe_unused.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Arnd Bergmann
d9a4d80bb3 net: hp100: remove unnecessary #ifdefs
commit 747a11279a442b913a57bf38934879babab3b58b upstream.

Building the hp100 ethernet driver causes warnings when both the PCI
and EISA drivers are disabled:

ethernet/hp/hp100.c: In function 'hp100_module_init':
ethernet/hp/hp100.c:3047:2: warning: label 'out3' defined but not used [-Wunused-label]
ethernet/hp/hp100.c: At top level:
ethernet/hp/hp100.c:2828:13: warning: 'cleanup_dev' defined but not used [-Wunused-function]

We can easily avoid the warnings and make the driver look slightly
nicer by removing the #ifdefs that check for the CONFIG_PCI and
CONFIG_EISA, as all the registration functions are designed to
have no effect when the buses are disabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Jun Nie
4b88c89bc2 dmaengine: zx: fix build warning
commit 067fdeb2f391bfa071f741a2b3eb74b8ff3785cd upstream.

Fix build warning that related to PAGE_SIZE. The maximum DMA
length has nothing to do with PAGE_SIZE, just use a fix number
for the definition.

drivers/dma/zx_dma.c: In function 'zx_dma_prep_memcpy':
drivers/dma/zx_dma.c:523:8: warning: division by zero [-Wdiv-by-zero]
drivers/dma/zx_dma.c: In function 'zx_dma_prep_slave_sg':
drivers/dma/zx_dma.c:567:11: warning: division by zero [-Wdiv-by-zero]

Signed-off-by: Jun Nie <jun.nie@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Arnd Bergmann
e787fce41c perf/x86: Shut up false-positive -Wmaybe-uninitialized warning
commit 11d8b05855f3749bcb6c57e2c4052921b9605c77 upstream.

The intialization function checks for various failure scenarios, but
unfortunately the compiler gets a little confused about the possible
combinations, leading to a false-positive build warning when
-Wmaybe-uninitialized is set:

  arch/x86/events/core.c: In function ‘init_hw_perf_events’:
  arch/x86/events/core.c:264:3: warning: ‘reg_fail’ may be used uninitialized in this function [-Wmaybe-uninitialized]
  arch/x86/events/core.c:264:3: warning: ‘val_fail’ may be used uninitialized in this function [-Wmaybe-uninitialized]
     pr_err(FW_BUG "the BIOS has corrupted hw-PMU resources (MSR %x is %Lx)\n",

We can't actually run into this case, so this shuts up the warning
by initializing the variables to a known-invalid state.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170719125310.2487451-2-arnd@arndb.de
Link: https://patchwork.kernel.org/patch/9392595/
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Arnd Bergmann
d3843789e7 wireless: cw1200: use __maybe_unused to hide pm functions_
commit 836856e3bd61d0644e5178a2c1b51d90459e2788 upstream.

The cw1200 uses #ifdef to check for CONFIG_PM, but then
uses SIMPLE_DEV_PM_OPS, which leaves the references out when
CONFIG_PM_SLEEP is not defined, so we get a warning with
PM=y && PM_SLEEP=n:

drivers/net/wireless/st/cw1200/cw1200_spi.c:450:12: error: 'cw1200_spi_suspend' defined but not used [-Werror=unused-function]

This removes the incorrect #ifdef and instead uses a __maybe_unused
annotation to let the compiler know it can silently drop
the function definition.

For the DEV_PM_OPS definition, we can use an IS_ENABLED() check
to avoid defining the structure when CONFIG_PM is not set without
the #ifdef.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Arnd Bergmann
6420c014ed cw1200: fix bogus maybe-uninitialized warning
commit 7fc1503c906f0fac62d3506a6e993e49fb996248 upstream.

On x86, the cw1200 driver produces a rather silly warning about the
possible use of the 'ret' variable without an initialization
presumably after being confused by the architecture specific definition
of WARN_ON:

drivers/net/wireless/st/cw1200/wsm.c: In function ‘wsm_handle_rx’:
drivers/net/wireless/st/cw1200/wsm.c:1457:9: error: ‘ret’ may be used uninitialized in this function [-Werror=maybe-uninitialized]

We have already checked that 'count' is larger than 0 here, so
we know that 'ret' is initialized. Changing the 'for' loop
into do/while also makes this clear to the compiler.

Suggested-by: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Arnd Bergmann
30ddc36cb7 v4l: remove MEDIA_TUNER dependency for VIDEO_TUNER
commit 7c8fe516bd81d991feb73ccd969ec29850af3013 upstream.

em28xx selects VIDEO_TUNER, which has a dependency on MEDIA_TUNER,
so we get a Kconfig warning if that is disabled:

warning: (VIDEO_PVRUSB2 && VIDEO_USBVISION && VIDEO_GO7007 && VIDEO_AU0828_V4L2 && VIDEO_CX231XX && VIDEO_TM6000 && VIDEO_EM28XX && VIDEO_IVTV && VIDEO_MXB && VIDEO_CX18 && VIDEO_CX23885 && VIDEO_CX88 && VIDEO_BT848 && VIDEO_SAA7134 && VIDEO_SAA7164) selects VIDEO_TUNER which has unmet direct dependencies (MEDIA_SUPPORT && MEDIA_TUNER)

VIDEO_TUNER does not actually depend on MEDIA_TUNER, and the
dependency does nothing except cause the above warning, so let's
remove it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:50 +01:00
Arnd Bergmann
a32040f7bb hdpvr: hide unused variable
commit b97baa3e22e18dac42001e665cf27ad1211bf878 upstream.

The i2c client pointer is only used when CONFIG_I2C is set, and
otherwise produces a compile-time warning:

drivers/media/usb/hdpvr/hdpvr-core.c: In function 'hdpvr_probe':
drivers/media/usb/hdpvr/hdpvr-core.c:276:21: error: unused variable 'client' [-Werror=unused-variable]

This uses the same #ifdef to hide the variable when the code using
it is hidden.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:49 +01:00
Thierry Reding
3d2ff1139d drm/gma500: Sanity-check pipe index
commit 4f250706211cdb949f7580d4fe4dd1fd646de693 upstream.

If the DSI output isn't connected, then mdfld_dsi_encoder_get_pipe()
will return -1. The mdfld_dsi_dp_mode_set() function doesn't properly
check for this condition and causes the following compiler warnings:

	  CC      drivers/gpu/drm/gma500/mdfld_dsi_dpi.o
	drivers/gpu/drm/gma500/mdfld_dsi_dpi.c: In function ‘mdfld_dsi_dpi_mode_set’:
	drivers/gpu/drm/gma500/mdfld_dsi_dpi.c:828:35: warning: array subscript is below array bounds [-Warray-bounds]
	  u32 pipeconf = dev_priv->pipeconf[pipe];
	                                   ^
	drivers/gpu/drm/gma500/mdfld_dsi_dpi.c:829:33: warning: array subscript is below array bounds [-Warray-bounds]
	  u32 dspcntr = dev_priv->dspcntr[pipe];
	                                 ^

Fix this by checking for a valid pipe before indexing the pipeconf and
dspcntr arrays.

Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Reviewed-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450178476-26284-2-git-send-email-boris.brezillon@free-electrons.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:49 +01:00
Heikki Krogerus
ab7b4a32b4 serial: 8250_mid: fix broken DMA dependency
commit 0ff4230584320b2153752ba54e2e8edbd6addf2c upstream.

In order to enable HSU DMA PCI driver, the HSU DMA Engine
must be enabled. This add a check for that.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:49 +01:00
Arnd Bergmann
8caadd7bf2 ASoC: rockchip: use __maybe_unused to hide st_irq_syscfg_resume
commit d8fc2198aab117a4bc16ee305caef19c4c7e7f5c upstream.

The rockchip spdif driver uses SIMPLE_DEV_PM_OPS to conditionally
set its power management functions, but we get a warning
about rk_spdif_runtime_resume being unused when CONFIG_PM is not
set:

sound/soc/rockchip/rockchip_spdif.c:67:12: error: 'rk_spdif_runtime_resume' defined but not used [-Werror=unused-function]

This adds a __maybe_unused annotation so the compiler knows
it can silently drop it instead of warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:03:49 +01:00