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| author |   Russell King <rmk+kernel@arm.linux.org.uk> | 2014-08-05 10:27:25 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-08-05 10:27:25 +0100 |
| commit | f15bdfe4fb264ac30d9c176f898cbd52cfd1ffa9 (patch) | |
| tree | d93b59190624c0df80854aff5078c588420c3516 /arch/arm/kernel/perf_event.c | |
| parent | Merge branch 'swp' (early part) into for-next (diff) | |
| parent | Merge tag 'nommu-for-rmk' of git://git.pengutronix.de/git/ukl/linux into devel-stable (diff) | |
| download | linux-dev-f15bdfe4fb264ac30d9c176f898cbd52cfd1ffa9.tar.xz linux-dev-f15bdfe4fb264ac30d9c176f898cbd52cfd1ffa9.zip | |
Merge branch 'devel-stable' into for-next
Conflicts:
arch/arm/kernel/perf_event_cpu.c
Diffstat (limited to 'arch/arm/kernel/perf_event.c')
| -rw-r--r-- | arch/arm/kernel/perf_event.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index ae3e216a52c2..266cba46db3e 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -560,11 +560,16 @@ user_backtrace(struct frame_tail __user *tail, struct perf_callchain_entry *entry) { struct frame_tail buftail; + unsigned long err; - /* Also check accessibility of one struct frame_tail beyond */ if (!access_ok(VERIFY_READ, tail, sizeof(buftail))) return NULL; - if (__copy_from_user_inatomic(&buftail, tail, sizeof(buftail))) + + pagefault_disable(); + err = __copy_from_user_inatomic(&buftail, tail, sizeof(buftail)); + pagefault_enable(); + + if (err) return NULL; perf_callchain_store(entry, buftail.lr); @@ -590,6 +595,10 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs) } perf_callchain_store(entry, regs->ARM_pc); + + if (!current->mm) + return; + tail = (struct frame_tail __user *)regs->ARM_fp - 1; while ((entry->nr < PERF_MAX_STACK_DEPTH) && |