lkml.org 
[lkml]   [2022]   [Feb]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] slab: remove __alloc_size attribute from __kmalloc_track_caller
On Fri, Feb 18, 2022 at 07:54:14PM +0100, Vlastimil Babka wrote:
> On 2/18/22 18:57, Greg Kroah-Hartman wrote:
> > On Fri, Feb 18, 2022 at 06:14:55PM +0100, Vlastimil Babka wrote:
> >> On 2/18/22 14:13, Greg Kroah-Hartman wrote:
> >> > Commit c37495d6254c ("slab: add __alloc_size attributes for better
> >> > bounds checking") added __alloc_size attributes to a bunch of kmalloc
> >> > function prototypes. Unfortunately the change to __kmalloc_track_caller
> >> > seems to cause clang to generate broken code and the first time this is
> >> > called when booting, the box will crash.
> >> >
> >> > While the compiler problems are being reworked and attempted to be
> >> > solved, let's just drop the attribute to solve the issue now. Once it
> >> > is resolved it can be added back.
> >>
> >> Could we instead wrap it in some #ifdef that' only true for clang build?
> >> That would make the workaround more precise and self-documented. Even
> >> better if it can trigger using clang version range and once a fixed
> >> clang version is here, it can be updated to stay true for older clangs.
> >
> > It's not doing all that much good like this, let's just remove it for
> > now until it does actually provide a benifit and not just crash the box :)
> >
> > This is only 1 function, that is used in only a very small number of
> > callers. I do not think it will be missed.
>
> Fair enough, added to the slab tree:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git/log/?h=for-5.17/fixup5
>

Thanks!

\
 
 \ /
  Last update: 2022-02-19 08:20    [W:0.080 / U:0.040 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site