mm: kmemleak_alloc_percpu() should follow the gfp from per_alloc()
Beginning at commit d52d3997f843 ("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>
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index ca9e5a5..cf79f11 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -930,12 +930,13 @@
* kmemleak_alloc_percpu - register a newly allocated __percpu object
* @ptr: __percpu pointer to beginning of the object
* @size: size of the object
+ * @gfp: flags used for kmemleak internal memory allocations
*
* This function is called from the kernel percpu allocator when a new object
- * (memory block) is allocated (alloc_percpu). It assumes GFP_KERNEL
- * allocation.
+ * (memory block) is allocated (alloc_percpu).
*/
-void __ref kmemleak_alloc_percpu(const void __percpu *ptr, size_t size)
+void __ref kmemleak_alloc_percpu(const void __percpu *ptr, size_t size,
+ gfp_t gfp)
{
unsigned int cpu;
@@ -948,7 +949,7 @@
if (kmemleak_enabled && ptr && !IS_ERR(ptr))
for_each_possible_cpu(cpu)
create_object((unsigned long)per_cpu_ptr(ptr, cpu),
- size, 0, GFP_KERNEL);
+ size, 0, gfp);
else if (kmemleak_early_log)
log_early(KMEMLEAK_ALLOC_PERCPU, ptr, size, 0);
}