commit 98dcea0cfd04e083ac74137ceb9a632604740e2d upstream.
liblockdep has been broken since commit 75dd602a5198 ("lockdep: Fix
lock_chain::base size"), as that adds a check that MAX_LOCK_DEPTH is
within the range of lock_chain::depth and in liblockdep it is much
too large.
That should have resulted in a compiler error, but didn't because:
- the check uses ARRAY_SIZE(), which isn't yet defined in liblockdep
so is assumed to be an (undeclared) function
- putting a function call inside a BUILD_BUG_ON() expression quietly
turns it into some nonsense involving a variable-length array
It did produce a compiler warning, but I didn't notice because
liblockdep already produces too many warnings if -Wall is enabled
(which I'll fix shortly).
Even before that commit, which reduced lock_chain::depth from 8 bits
to 6, MAX_LOCK_DEPTH was too large.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/20170525130005.5947-3-alexander.levin@verizon.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It seems that newer gcc complains about lack of explicit declaration for some
of the API we use, add it in.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Commit 63f9a7fde7 "asmlinkage: Make lockdep_sys_exit asmlinkage" has added
asmlinkage annotation to lockdep_sys_exit, which broke build of liblockdep.
Since we don't need asmlinkage in liblockep, just ignore it.
Reported-by: Eunbong Song <eunb.song@samsung.com>
Reported-by: Robin Hack <rhack@redhat.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
kernel/locking/lockdep.c deals with validating locking scenarios for
various architectures supported by the kernel. There isn't
anything kernel specific going on in lockdep, and when we
compare userspace to other architectures that don't have to deal
with irqs such as s390, they become all too similar.
We wrap kernel/locking/lockdep.c and include/linux/lockdep.h with
several headers which allow us to build and use lockdep from
userspace. We don't touch the kernel code itself which means
that any work done on lockdep in the kernel will automatically
benefit userspace lockdep as well!
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/1371163284-6346-3-git-send-email-sasha.levin@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
