[PATCH 4.20 051/145] s390/pci: fix sleeping in atomic during hotplug

From: Greg Kroah-Hartman
Date: Mon Jan 07 2019 - 07:41:52 EST

4.20-stable review patch. If anyone has any objections, please let me know.


From: Sebastian Ott <sebott@xxxxxxxxxxxxx>

commit 98dfd32620e970eb576ebce5ea39d905cb005e72 upstream.

When triggered by pci hotplug (PEC 0x306) clp_get_state is called
with spinlocks held resulting in the following warning:

zpci: n/a: Event 0x306 reconfigured PCI function 0x0
BUG: sleeping function called from invalid context at mm/page_alloc.c:4324
in_atomic(): 1, irqs_disabled(): 0, pid: 98, name: kmcheck
2 locks held by kmcheck/98:

Change the allocation to use GFP_ATOMIC.

Cc: stable@xxxxxxxxxxxxxxx # 4.13+
Signed-off-by: Sebastian Ott <sebott@xxxxxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

arch/s390/pci/pci_clp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/s390/pci/pci_clp.c
+++ b/arch/s390/pci/pci_clp.c
@@ -436,7 +436,7 @@ int clp_get_state(u32 fid, enum zpci_sta
struct clp_state_data sd = {fid, ZPCI_FN_STATE_RESERVED};
int rc;

- rrb = clp_alloc_block(GFP_KERNEL);
+ rrb = clp_alloc_block(GFP_ATOMIC);
if (!rrb)
return -ENOMEM;