Revert "s390/pci: remove bit_lock usage in interrupt handler"
authorSebastian Ott <sebott@linux.ibm.com>
Tue, 29 Jan 2019 14:15:18 +0000 (15:15 +0100)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Thu, 7 Feb 2019 10:56:29 +0000 (11:56 +0100)
commit614db26954ff08fa8e92b04100e31ebc04b817cf
treeb3036d1e33eb2b7559e6564f11651774fc9c7eaa
parent8f9aca0c45322a807a343fc32f95f2500f83b9ae
Revert "s390/pci: remove bit_lock usage in interrupt handler"

This reverts commit 9594ca6b87d9f11e9f14ac31581e0e5d79a8e839.

With the handle_simple_irq irq_flow_handler it must be ensured to
not call generic_handle_irq with the same IRQ number on 2 CPUs at
the same time (interrupts are floating on s390).
Contrary to my initial investigation the irq_desc's lock usage in
handle_simple_irq does not ensure this. Thus re-introduce the bit-
lock usage in s390's pci handler.

Reported-by: Ursula Braun <ubraun@linux.ibm.com>
Reported-by: Alexander Schmidt <alexs@linux.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch/s390/pci/pci.c