[lkml]   [2008]   [Jan]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
SubjectRe: [PATCH] Only print SCSI data direction warning once for a command

> to the log because they come from printk_ratelimit(). So all you've
> done is halved the volume of flow to the logs and left a dangling printk
> suppressed message that keeps spewing, so I don't think the patch even
> does what you describe it as doing ... if you reverse the order of the
> operands in the if() it will ...

Here's an updated patch with the reversed order.



Only print SCSI data direction warning once for a command v2

When I use cdparanoia my logs get spammed a lot by

printk: 464 messages suppressed.
sg_write: data in/out 30576/30576 bytes for SCSI command 0xbe--guessing data in;
program cdparanoia not setting count and/or reply_len properly
printk: 1078 messages suppressed.

and many more of those. With this patch the message is only printed once
for a command in a row.

v1->v2: Prevent rate limit messages too (pointed out by jejb)

Signed-off-by: Andi Kleen <>

drivers/scsi/sg.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

Index: linux/drivers/scsi/sg.c
--- linux.orig/drivers/scsi/sg.c
+++ linux/drivers/scsi/sg.c
@@ -602,8 +602,9 @@ sg_write(struct file *filp, const char _
* but is is possible that the app intended SG_DXFER_TO_DEV, because there
* is a non-zero input_size, so emit a warning.
- if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV)
- if (printk_ratelimit())
+ if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
+ static char cmd[TASK_COMM_LEN];
+ if (strcmp(current->comm, cmd) && printk_ratelimit()) {
"sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
"guessing data in;\n" KERN_WARNING " "
@@ -611,6 +612,9 @@ sg_write(struct file *filp, const char _
old_hdr.reply_len - (int)SZ_SG_HEADER,
input_size, (unsigned int) cmnd[0],
+ strcpy(cmd, current->comm);
+ }
+ }
k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
return (k < 0) ? k : count;

 \ /
  Last update: 2008-01-13 17:45    [W:0.047 / U:0.644 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site