Commit ce4dda3f authored Dec 02, 2016 by Martin Schwidefsky

s390: fix machine check panic stack switch



For system damage machine checks or machine checks due to invalid PSW
fields the system will be stopped. In order to get an oops message out
before killing the system the machine check handler branches to
.Lmcck_panic, switches to the panic stack and then does the usual
machine check handling.

The switch to the panic stack is incomplete, the stack pointer in %r15
is replaced, but the pt_regs pointer in %r11 is not. The result is
a program check which will kill the system in a slightly different way.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

parent db7ad636

arch/s390/kernel/entry.S

+1 −1

Original line number	Diff line number	Diff line
		@@ -958,7 +958,7 @@ ENTRY(mcck_int_handler)

		.Lmcck_panic:
		lg %r15,__LC_PANIC_STACK
		aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
		la %r11,STACK_FRAME_OVERHEAD(%r15)
		j .Lmcck_skip

		#

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