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FRV: Prevent syscall exit tracing and notify_resume at end of kernel exceptions

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Move the test for kernel mode processing from do_signal() into entry.S to also
prevent system call exit tracing and userspace resumption notification handling
happening when returning from kernel exceptions.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
David Howells 2012-05-01 19:44:14 +01:00 committed by Al Viro
parent efee984c27
commit 137c3c469f
2 changed files with 3 additions and 11 deletions
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4
arch/frv/kernel/entry.S
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@ -1163,7 +1163,9 @@ __syscall_trace_entry:
# perform syscall exit tracing
__syscall_exit_work:
LEDS 0x6340
andicc gr4,#_TIF_SYSCALL_TRACE,gr0,icc0
andicc gr22,#PSR_PS,gr0,icc1 ; don't handle on return to kernel mode
andicc.p gr4,#_TIF_SYSCALL_TRACE,gr0,icc0
bne icc1,#0,__entry_return_direct
beq icc0,#1,__entry_work_pending
movsg psr,gr23

10
arch/frv/kernel/signal.c
View File

@ -474,18 +474,8 @@ static void do_signal(void)
{
struct k_sigaction ka;
siginfo_t info;
sigset_t *oldset;
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(__frame))
return;
signr = get_signal_to_deliver(&info, &ka, __frame, NULL);
if (signr > 0) {
handle_signal(signr, &info, &ka);