Commit c63b0084 authored Jan 07, 2025 by Easwar Hariharan Committed by Wen Zhiwei Mar 21, 2025

scsi: storvsc: Ratelimit warning logs to prevent VM denial of service

stable inclusion
from stable-v6.6.75
commit 088bde862f8d3d0fc52e40e66a0484a246837087
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IBSPQB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=088bde862f8d3d0fc52e40e66a0484a246837087

--------------------------------

commit d2138eab8cde61e0e6f62d0713e45202e8457d6d upstream.

If there's a persistent error in the hypervisor, the SCSI warning for
failed I/O can flood the kernel log and max out CPU utilization,
preventing troubleshooting from the VM side. Ratelimit the warning so
it doesn't DoS the VM.

Closes: https://github.com/microsoft/WSL/issues/9173


Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250107-eahariha-ratelimit-storvsc-v1-1-7fc193d1f2b0@linux.microsoft.com


Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Wen Zhiwei <wenzhiwei@kylinos.cn>

parent 3287794d

drivers/scsi/storvsc_drv.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -171,6 +171,12 @@ do { \
		dev_warn(&(dev)->device, fmt, ##__VA_ARGS__); \
		} while (0)

		#define storvsc_log_ratelimited(dev, level, fmt, ...) \
		do { \
		if (do_logging(level)) \
		dev_warn_ratelimited(&(dev)->device, fmt, ##__VA_ARGS__); \
		} while (0)

		struct vmscsi_request {
		u16 length;
		u8 srb_status;
		@@ -1177,7 +1183,7 @@ static void storvsc_on_io_completion(struct storvsc_device *stor_device,
		int loglevel = (stor_pkt->vm_srb.cdb[0] == TEST_UNIT_READY) ?
		STORVSC_LOGGING_WARN : STORVSC_LOGGING_ERROR;

		storvsc_log(device, loglevel,
		storvsc_log_ratelimited(device, loglevel,
		"tag#%d cmd 0x%x status: scsi 0x%x srb 0x%x hv 0x%x\n",
		scsi_cmd_to_rq(request->cmd)->tag,
		stor_pkt->vm_srb.cdb[0],