lkml.org 
[lkml]   [2010]   [May]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [Regression] Crash in load_module() while freeing args
Date
On Fri, 28 May 2010 04:16:02 am Brandon Philips wrote:
> On 14:56 Thu 27 May 2010, Rusty Russell wrote:
> > On Thu, 27 May 2010 08:26:25 am Rafael J. Wysocki wrote:
> > > On Wednesday 26 May 2010, Rusty Russell wrote:
> > > > I suspect that the increased parallelism enabled by this patch uncovered this
> > > > bug. Does this fix it?
> > >
> > > Since the commit has been reverted, do you still want me to test this patch?
> > > Quite frankly I'd prefer to test a complete replacement for that commit on top
> > > of current -git.
> >
> > OK, combo meal deal below, against Linus' latest. I'd really appreciate
> > a report, since AFAIK you're the only one hitting it, and only when that
> > other (now reverted) patch was applied.
>
> I tested this patch on my machine on top of Linus's latest and it
> fixes the issue. Without the patch and using Linus's latest I
> reproduce the original issue:
>
> [ 60.836022] bnx2: gave up waiting for init of module libcrc32c.
> [ 60.847997] bnx2: Unknown symbol crc32c
>
> Note: Again, since I don't have bnx2x hardware I forced bnx2.ko to
> depend on libcrc32c as bnx2x does:
> http://ifup.org/~philips/review/bnx2-hack-to-use-libcrc32c.patch
>
> > As an side to Brandon: I can see how my patch fixed an explicit
> > request_module inside module_init (that's how I tested it). I can't
> > see how we have a problem with an implicit dependency such as
> > bne2x->crc32. Modules go into the live state without retaking the
> > lock.
>
> libcrc32c is doing an explicit request_module inside of its
> module_init. Follow the call chain in libcrc32c_mod_init()

Thanks for confirmation, I figured that must be the case as I pondered
it on the weekend after sending my query.

Linus didn't like dropping the lock, so I'll create a more ambitious patch
which reduces the lock coverage to those places which really need it.

Cheers,
Rusty.




\
 
 \ /
  Last update: 2010-05-31 11:43    [W:0.126 / U:0.340 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site