alistair23-linux/include/linux/kmemleak.h
Larry Finger 8a8c35fadf mm: kmemleak_alloc_percpu() should follow the gfp from per_alloc()
Beginning at commit d52d3997f8 ("ipv6: Create percpu rt6_info"), the
following INFO splat is logged:

  ===============================
  [ INFO: suspicious RCU usage. ]
  4.1.0-rc7-next-20150612 #1 Not tainted
  -------------------------------
  kernel/sched/core.c:7318 Illegal context switch in RCU-bh read-side critical section!
  other info that might help us debug this:
  rcu_scheduler_active = 1, debug_locks = 0
   3 locks held by systemd/1:
   #0:  (rtnl_mutex){+.+.+.}, at: [<ffffffff815f0c8f>] rtnetlink_rcv+0x1f/0x40
   #1:  (rcu_read_lock_bh){......}, at: [<ffffffff816a34e2>] ipv6_add_addr+0x62/0x540
   #2:  (addrconf_hash_lock){+...+.}, at: [<ffffffff816a3604>] ipv6_add_addr+0x184/0x540
  stack backtrace:
  CPU: 0 PID: 1 Comm: systemd Not tainted 4.1.0-rc7-next-20150612 #1
  Hardware name: TOSHIBA TECRA A50-A/TECRA A50-A, BIOS Version 4.20   04/17/2014
  Call Trace:
    dump_stack+0x4c/0x6e
    lockdep_rcu_suspicious+0xe7/0x120
    ___might_sleep+0x1d5/0x1f0
    __might_sleep+0x4d/0x90
    kmem_cache_alloc+0x47/0x250
    create_object+0x39/0x2e0
    kmemleak_alloc_percpu+0x61/0xe0
    pcpu_alloc+0x370/0x630

Additional backtrace lines are truncated.  In addition, the above splat
is followed by several "BUG: sleeping function called from invalid
context at mm/slub.c:1268" outputs.  As suggested by Martin KaFai Lau,
these are the clue to the fix.  Routine kmemleak_alloc_percpu() always
uses GFP_KERNEL for its allocations, whereas it should follow the gfp
from its callers.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: <stable@vger.kernel.org>	[3.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-24 17:49:46 -07:00

113 lines
3 KiB
C

/*
* include/linux/kmemleak.h
*
* Copyright (C) 2008 ARM Limited
* Written by Catalin Marinas <catalin.marinas@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef __KMEMLEAK_H
#define __KMEMLEAK_H
#include <linux/slab.h>
#ifdef CONFIG_DEBUG_KMEMLEAK
extern void kmemleak_init(void) __ref;
extern void kmemleak_alloc(const void *ptr, size_t size, int min_count,
gfp_t gfp) __ref;
extern void kmemleak_alloc_percpu(const void __percpu *ptr, size_t size,
gfp_t gfp) __ref;
extern void kmemleak_free(const void *ptr) __ref;
extern void kmemleak_free_part(const void *ptr, size_t size) __ref;
extern void kmemleak_free_percpu(const void __percpu *ptr) __ref;
extern void kmemleak_update_trace(const void *ptr) __ref;
extern void kmemleak_not_leak(const void *ptr) __ref;
extern void kmemleak_ignore(const void *ptr) __ref;
extern void kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp) __ref;
extern void kmemleak_no_scan(const void *ptr) __ref;
static inline void kmemleak_alloc_recursive(const void *ptr, size_t size,
int min_count, unsigned long flags,
gfp_t gfp)
{
if (!(flags & SLAB_NOLEAKTRACE))
kmemleak_alloc(ptr, size, min_count, gfp);
}
static inline void kmemleak_free_recursive(const void *ptr, unsigned long flags)
{
if (!(flags & SLAB_NOLEAKTRACE))
kmemleak_free(ptr);
}
static inline void kmemleak_erase(void **ptr)
{
*ptr = NULL;
}
#else
static inline void kmemleak_init(void)
{
}
static inline void kmemleak_alloc(const void *ptr, size_t size, int min_count,
gfp_t gfp)
{
}
static inline void kmemleak_alloc_recursive(const void *ptr, size_t size,
int min_count, unsigned long flags,
gfp_t gfp)
{
}
static inline void kmemleak_alloc_percpu(const void __percpu *ptr, size_t size,
gfp_t gfp)
{
}
static inline void kmemleak_free(const void *ptr)
{
}
static inline void kmemleak_free_part(const void *ptr, size_t size)
{
}
static inline void kmemleak_free_recursive(const void *ptr, unsigned long flags)
{
}
static inline void kmemleak_free_percpu(const void __percpu *ptr)
{
}
static inline void kmemleak_update_trace(const void *ptr)
{
}
static inline void kmemleak_not_leak(const void *ptr)
{
}
static inline void kmemleak_ignore(const void *ptr)
{
}
static inline void kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp)
{
}
static inline void kmemleak_erase(void **ptr)
{
}
static inline void kmemleak_no_scan(const void *ptr)
{
}
#endif /* CONFIG_DEBUG_KMEMLEAK */
#endif /* __KMEMLEAK_H */