Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 21c1176a authored Apr 28, 2012 by Al Viro

arm: if we get into work_pending while returning to kernel mode, just go away



checking in do_signal() is pointless - if we get there with !user_mode(regs)
(and we might), we'll end up looping indefinitely.  Check in work_pending
and break out of the loop if so.

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

parent d9be5ea6

arch/arm/kernel/entry-common.S

+3 −0

Original line number	Diff line number	Diff line
		@@ -56,7 +56,10 @@ work_pending:
		/*
		* TIF_SIGPENDING or TIF_NOTIFY_RESUME must've been set if we got here
		*/
		ldr r2, [sp, #S_PSR]
		mov r0, sp @ 'regs'
		tst r2, #15 @ are we returning to user mode?
		bne no_work_pending @ no? just leave, then...
		mov r2, why @ 'syscall'
		tst r1, #_TIF_SIGPENDING @ delivering a signal?
		movne why, #0 @ prevent further restarts

arch/arm/kernel/signal.c

+0 −9

Original line number	Diff line number	Diff line
		@@ -608,15 +608,6 @@ static void do_signal(struct pt_regs *regs, int syscall)
		siginfo_t info;
		int signr;

		/*
		* We want the common case to go fast, which
		* is why we may in certain cases get here from
		* kernel mode. Just return without doing anything
		* if so.
		*/
		if (!user_mode(regs))
		return;

		/*
		* If we were from a system call, check for system call restarting...
		*/