tree 92601341680bf89e42ed0073bd5086d16405356c
parent 35ac734f72d846f250c0344913a91f954ea764c3
author Martin Schwidefsky <schwidefsky@de.ibm.com> 1270813380 +0200
committer Martin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com> 1270813382 +0200

[S390] fix io_return critical section cleanup

If a machine check interrupts the io interrupt handler on one of the
instructions between io_return and io_leave the critical section
cleanup code will move the return psw to io_work_loop. By doing that
the switch from the asynchronous interrupt stack to the process stack
is skipped. If e.g. TIF_NEED_RESCHED is set things break because
the scheduler is called with the asynchronous interrupts stack.
Moving the psw back to io_return instead fixes the problem.

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