On Fri, 2018-04-06 at 21:03 -0400, Wakko Warner wrote: > Bart Van Assche wrote: > > On Thu, 2018-04-05 at 22:06 -0400, Wakko Warner wrote: > > > 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): > > > > git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > > git bisect start > > git bisect bad v4.10 > > git bisect good v4.9 > > > > and then build the kernel, install it, boot the kernel and test it. > > Depending on the result, run either git bisect bad or git bisect good and > > keep going until git bisect comes to a conclusion. This can take an hour or > > more. > > I have 1 question. Should make clean be done between tests? My box > compiles the whole kernel in 2 minutes.
If you trust that the build system will figure out all dependencies then running make clean is not necessary. Personally I always run make clean during a bisect before rebuilding the kernel because if a header file has changed in e.g. the block layer a huge number of files has to be rebuilt anyway. Bart.