| Message ID | 1403881067-22690-2-git-send-email-jean.pihet@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jun 27, 2014 at 03:57:45PM +0100, Jean Pihet wrote: > An event may occur when an mm is already released. > > As per commit 20afc60f892d285fde179ead4b24e6a7938c2f1b > 'x86, perf: Check that current->mm is alive before getting user callchain' > > Signed-off-by: Jean Pihet <jean.pihet@linaro.org> > Cc: Will Deacon <will.deacon@arm.com> > --- Acked-by: Will Deacon <will.deacon@arm.com> > arch/arm/kernel/perf_event.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c > index 4238bcb..6493c4c 100644 > --- a/arch/arm/kernel/perf_event.c > +++ b/arch/arm/kernel/perf_event.c > @@ -590,6 +590,10 @@ 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) && > -- > 1.8.1.2 > >
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 4238bcb..6493c4c 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -590,6 +590,10 @@ 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) &&
An event may occur when an mm is already released. As per commit 20afc60f892d285fde179ead4b24e6a7938c2f1b 'x86, perf: Check that current->mm is alive before getting user callchain' Signed-off-by: Jean Pihet <jean.pihet@linaro.org> Cc: Will Deacon <will.deacon@arm.com> --- arch/arm/kernel/perf_event.c | 4 ++++ 1 file changed, 4 insertions(+)