Re: [PATCH 3.12-rc7] KVM: Fix modprobe failure for kvm_intel/kvm_amd

From: Raghavendra K T
Date: Wed Oct 30 2013 - 10:00:23 EST

This is a multi-part message in MIME format.On 10/30/2013 01:03 AM, Linus Torvalds wrote:
On Tue, Oct 29, 2013 at 12:27 PM, Raghavendra K T
<raghavendra.kt@xxxxxxxxxxxxxxxxxx> wrote:

Could one solution be cascading actual error
that is lost in fs/debugfs/inode.c:__create_file(), so that we could
take correct action in case of failure of debugfs_create_dir()?

(ugly side is we increase total number of params for __create_file to
6). or I hope there could be some better solution.

The solution to this would be to simply return an error-pointer. See
<linux/err.h>. That's what we do for most complex subsystems that
return a pointer to a struct: rather than returning "NULL" as an
error, return the actual error number encoded in the pointer itself.

Thank you Linus. Yes, this would have been ideal.

But that would require every user of debugfs_create_dir() to be
updated to check errors using IS_ERR() instead of checking against
NULL, and there's quite a few of them.

So I think just making the error be EEXIST is a simpler solution right now.

I had below patch, and just before sending as formal mail I saw
Paolo's pull request which already took care of it.