Re: [PATCH v2] xen/arm: Avoid overflow using MIDR_IMPLEMENTOR_MASK

[Julien Grall <julien@xxxxxxx>]

Hi Catalin,

On 10/05/2022 09:55, Catalin Marinas wrote:
> On Tue, May 10, 2022 at 09:27:29AM +0100, Julien Grall wrote:
> > Hi,
> >
> > On 10/05/2022 07:49, Michal Orzel wrote:
> > > On 05.05.2022 14:13, Catalin Marinas wrote:
> > > > On Thu, May 05, 2022 at 01:59:06PM +0200, Michal Orzel wrote:
> > > > > Value of macro MIDR_IMPLEMENTOR_MASK exceeds the range of integer
> > > > > and can lead to overflow. Currently there is no issue as it is used
> > > > > in an expression implicitly casted to u32 in MIDR_IS_CPU_MODEL_RANGE.
> > > > > To avoid possible problems, fix the macro.
> > > > >
> > > > > Signed-off-by: Michal Orzel <michal.orzel@xxxxxxx>
> > > > > Link: https://lore.kernel.org/r/20220426070603.56031-1-michal.orzel@xxxxxxx
> > > > > Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
> > > > > Origin: git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git (48e6f22e25a4)
> > > > > ---
> > > > > Changes since v1:
> > > > > - add Origin tag as the patch was merged in upstream arm64 linux tree
> > > > Note that there's always a risk that the commit Id will be changed
> > > > before it hits mainline (Linus' tree).
> > > This commit is now in linux-next:
> > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=48e6f22e25a44e43952db5fbb767dea0c9319cb2
> > > so we can be sure that the SHA will stay unmodified there (and will be the same 
> > > in Linus' tree).
> > AFAIK, linux-next branch is just a merge of all the maintainers branch and
> > often rewritten. So there are no guarantee a commit id is valid until it
> > reached Linus' tree.
> Indeed. While I try not to rebase it, it may happen occasionally.
>
> > > Question to maintainers:
> > > Do you want me to update Origin to point to linux-next?
> > So we have a link to the patch and a name. This should be sufficient to find
> > the commit.
> >
> > Therefore, I would simply on top of Origin:
> Yeah, just keep the link to the mailing list. I guess you can drop my
> Singed-off-by as well if it appears to be picked from the list rather
> than the kernel repo. If you want an ack:
>
> Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
I have done what you suggested and committed. Thanks!

Cheers,

--
Julien Grall