[PATCH 3.2 68/87] xtensa: don't use alternate signal stack on threads

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



3.2.53-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Baruch Siach <baruch@xxxxxxxxxx>

commit cba9a90053e3b7973eff4f1946f33032e98eeed5 upstream.

According to create_thread(3): "The new thread does not inherit the creating
thread's alternate signal stack". Since commit f9a3879a (Fix sigaltstack
corruption among cloned threads), current->sas_ss_size is set to 0 for cloned
processes sharing VM with their parent. Don't use the (nonexistent) alternate
signal stack in this case. This has been broken since commit 29c4dfd9 ([XTENSA]
Remove non-rt signal handling).

Fixes the SA_ONSTACK part of the nptl/tst-cancel20 test from uClibc.

Signed-off-by: Baruch Siach <baruch@xxxxxxxxxx>
Signed-off-by: Max Filippov <jcmvbkbc@xxxxxxxxx>
Signed-off-by: Chris Zankel <chris@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 arch/xtensa/kernel/signal.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/xtensa/kernel/signal.c
+++ b/arch/xtensa/kernel/signal.c
@@ -346,7 +346,7 @@ static void setup_frame(int sig, struct
 
 	sp = regs->areg[1];
 
-	if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp)) {
+	if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && sas_ss_flags(sp) == 0) {
 		sp = current->sas_ss_sp + current->sas_ss_size;
 	}
 

--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]