scsi: storvsc: Ratelimit warning logs to prevent VM denial of service
PATCH 1/1 scsi: storvsc: Ratelimit warning logs to prevent VM denial of service
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.
--- drivers/scsi/storvsc_drv.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
drivers/scsi/storvsc_drv.c +7 -1
@@ -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],
Signature · 1 line
2.43.0
Greg KH
maintainerQuoted 13 lines · Easwar Hariharan
commit
d2138eab8cde61e0e6f62d0713e45202e8457d6dupstreamIf 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.
Signed-off-by Easwar Hariharan <[email protected]>Link https://lore.kernel.org/r/20250107-eahariha-ratelimit-storvsc-v1-1-7fc193d1f2b0@linux.microsoft.com open hereReviewed-by Michael Kelley <[email protected]>Signed-off-by Martin K. Petersen <[email protected]>Signed-off-by Easwar Hariharan <[email protected]>
Quoted 3 lines
--- drivers/scsi/storvsc_drv.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
What about 6.13.y?
Quoted 18 lines · Greg KH
Quoted 13 lines · Easwar Hariharan
commit
d2138eab8cde61e0e6f62d0713e45202e8457d6dupstreamIf 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.
Signed-off-by Easwar Hariharan <[email protected]>Link https://lore.kernel.org/r/20250107-eahariha-ratelimit-storvsc-v1-1-7fc193d1f2b0@linux.microsoft.com open hereReviewed-by Michael Kelley <[email protected]>Signed-off-by Martin K. Petersen <[email protected]>Signed-off-by Easwar Hariharan <[email protected]>Quoted 3 lines
--- drivers/scsi/storvsc_drv.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
Quoted 2 lines
What about 6.13.y?
Yes, needs a backport to that too, another miss on my part. :(
Would you rather I send it after rc1 is tagged, or now for completeness?
- Easwar (he/him)
Greg KH
maintainerQuoted 19 lines · Easwar Hariharan
Quoted 18 lines · Greg KH
Quoted 16 lines · Easwar Hariharan
commit
d2138eab8cde61e0e6f62d0713e45202e8457d6dupstreamIf 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.
Signed-off-by Easwar Hariharan <[email protected]>Link https://lore.kernel.org/r/20250107-eahariha-ratelimit-storvsc-v1-1-7fc193d1f2b0@linux.microsoft.com open hereReviewed-by Michael Kelley <[email protected]>Signed-off-by Martin K. Petersen <[email protected]>Signed-off-by Easwar Hariharan <[email protected]>--- drivers/scsi/storvsc_drv.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
Quoted 6 lines
Quoted 2 lines
What about 6.13.y?
Yes, needs a backport to that too, another miss on my part. :(
Would you rather I send it after rc1 is tagged, or now for completeness?
Whenever you have it, we can't apply any of these until -rc1 is out.
thanks,
greg k-h
[ Sasha's backport helper bot ]
Hi,
The upstream commit SHA1 provided is correct: d2138eab8cde61e0e6f62d0713e45202e8457d6d
Status in newer kernel trees:
6.13.y | Branch not found
6.12.y | Not found
Note: The patch differs from the upstream commit:
---
1: d2138eab8cde6 ! 1: 6ee86d3429520 scsi: storvsc: Ratelimit warning logs to prevent VM denial of service
@@ Metadata
## Commit message ##
scsi: storvsc: Ratelimit warning logs to prevent VM denial of service
+ 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
@@ Commit message
+ Signed-off-by: Easwar Hariharan <[email protected]>
## drivers/scsi/storvsc_drv.c ##
@@ drivers/scsi/storvsc_drv.c: do { \
---
Results of testing on various branches:
| Branch | Patch Apply | Build Test | |---------------------------|-------------|------------| | stable/linux-6.12.y | Success | Success |