do_work_pending() may be called on IRQ, exception or syscall exit (for reschedule, signal handling, etc.) , but user_enter() may have already been called (e.g. by syscall return path.)
Since do_work_pending() is still in kernel mode, keep context_tracker up to date by using user_exit/user_enter.
Based on commit edf55fda35c7dc7f2d9241c3abaddaf759b457c6 (x86: Exit RCU extended QS on notify resume)
Signed-off-by: Kevin Hilman khilman@linaro.org --- arch/arm/kernel/signal.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 296786b..42514fd 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -12,6 +12,7 @@ #include <linux/personality.h> #include <linux/uaccess.h> #include <linux/tracehook.h> +#include <linux/context_tracking.h>
#include <asm/elf.h> #include <asm/cacheflush.h> @@ -575,12 +576,15 @@ static int do_signal(struct pt_regs *regs, int syscall) asmlinkage int do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) { + int retval = 0; + + user_exit(); do { if (likely(thread_flags & _TIF_NEED_RESCHED)) { schedule(); } else { if (unlikely(!user_mode(regs))) - return 0; + break; local_irq_enable(); if (thread_flags & _TIF_SIGPENDING) { int restart = do_signal(regs, syscall); @@ -590,7 +594,8 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) * Deal with it without leaving * the kernel space. */ - return restart; + retval = restart; + break; } syscall = 0; } else { @@ -601,5 +606,6 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) local_irq_disable(); thread_flags = current_thread_info()->flags; } while (thread_flags & _TIF_WORK_MASK); - return 0; + user_enter(); + return retval; }