From 3d708895325b78506e8daf00ef31549476e8586a Mon Sep 17 00:00:00 2001 From: Qian Cai Date: Wed, 28 Aug 2019 17:39:43 -0400 Subject: [PATCH] iommu/amd: Silence warnings under memory pressure 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: 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 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 Signed-off-by: Joerg Roedel --- 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 008da21a2592..d365ee449a2c 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -2547,7 +2547,9 @@ 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;