lkml.org 
[lkml]   [2019]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH AUTOSEL 4.19 095/128] iommu/amd: Silence warnings under memory pressure
Date
From: Qian Cai <cai@lca.pw>

[ Upstream commit 3d708895325b78506e8daf00ef31549476e8586a ]

When running heavy memory pressure workloads, the system is throwing
endless warnings,

smartpqi 0000:23:00.0: AMD-Vi: IOMMU mapping error in map_sg (io-pages:
5 reason: -12)
Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40
07/10/2019
swapper/10: page allocation failure: order:0, mode:0xa20(GFP_ATOMIC),
nodemask=(null),cpuset=/,mems_allowed=0,4
Call Trace:
<IRQ>
dump_stack+0x62/0x9a
warn_alloc.cold.43+0x8a/0x148
__alloc_pages_nodemask+0x1a5c/0x1bb0
get_zeroed_page+0x16/0x20
iommu_map_page+0x477/0x540
map_sg+0x1ce/0x2f0
scsi_dma_map+0xc6/0x160
pqi_raid_submit_scsi_cmd_with_io_request+0x1c3/0x470 [smartpqi]
do_IRQ+0x81/0x170
common_interrupt+0xf/0xf
</IRQ>

because the allocation could fail from iommu_map_page(), and the volume
of this call could be huge which may generate a lot of serial console
output and cosumes all CPUs.

Fix it by silencing the warning in this call site, and there is still a
dev_err() later to notify the failure.

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/amd_iommu.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 8d9920ff41344..b892637c320bc 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2533,7 +2533,9 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,

bus_addr = address + s->dma_address + (j << PAGE_SHIFT);
phys_addr = (sg_phys(s) & PAGE_MASK) + (j << PAGE_SHIFT);
- ret = iommu_map_page(domain, bus_addr, phys_addr, PAGE_SIZE, prot, GFP_ATOMIC);
+ ret = iommu_map_page(domain, bus_addr, phys_addr,
+ PAGE_SIZE, prot,
+ GFP_ATOMIC | __GFP_NOWARN);
if (ret)
goto out_unmap;

--
2.20.1
\
 
 \ /
  Last update: 2019-09-22 20:57    [W:0.345 / U:0.976 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site