]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
kernel: printk: specify alignment for struct printk_log
authorAndrey Ryabinin <aryabinin@virtuozzo.com>
Wed, 20 Jan 2016 23:00:48 +0000 (15:00 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 21 Jan 2016 01:09:18 +0000 (17:09 -0800)
commit5c9cf8af2e77388f1da81c39237fb4f20c2f85d5
tree630e93c92d8310383d1870df818a3e7b29787005
parent41662f5cc55335807d39404371cfcbb1909304c4
kernel: printk: specify alignment for struct printk_log

On architectures that have support for efficient unaligned access struct
printk_log has 4-byte alignment.  Specify alignment attribute in type
declaration.

The whole point of this patch is to fix deadlock which happening when
UBSAN detects unaligned access in printk() thus UBSAN recursively calls
printk() with logbuf_lock held by top printk() call.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yury Gribov <y.gribov@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Kostya Serebryany <kcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/printk/printk.c