Bart Van Assche wrote:

On Thu, 2018-04-05 at 22:06 -0400, Wakko Warner wrote:

quoted

I know now why scsi_print_command isn't doing anything.  cmd->cmnd is null.
I added a dev_printk in scsi_print_command where the 2 if statements return.
Logs:
[  29.866415] sr 3:0:0:0: cmd->cmnd is NULL

That's something that should never happen. As one can see in
scsi_setup_scsi_cmnd() and scsi_setup_fs_cmnd() both functions initialize
that pointer. Since I have not yet been able to reproduce myself what you
reported, would it be possible for you to bisect this issue? You will need
to follow something like the following procedure (see also
https://git-scm.com/docs/git-bisect):

After doing 3 successful compiles with good/bad, I got this error and was
not able to compile any more kernels:
  CC      scripts/mod/devicetable-offsets.s
scripts/mod/empty.c:1:0: error: code model kernel does not support PIC mode
 /* empty file to figure out endianness / word size */
 
scripts/mod/devicetable-offsets.c:1:0: error: code model kernel does not support PIC mode
 #include <linux/kbuild.h>
 
scripts/Makefile.build:153: recipe for target 'scripts/mod/devicetable-offsets.s' failed

I don't think it found the bad commit.

-- 
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 million bugs.