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[ 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>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.