Re: NULL ptr deref in acpi_idle_enter+0x46/0x100

[Rafael J. Wysocki]

On Tue, Nov 25, 2025 at 8:55 AM Borislav Petkov <bp@xxxxxxxxx> wrote:
>
> On Mon, Nov 24, 2025 at 09:00:19PM +0100, Borislav Petkov wrote:
> > Hey,
> >
> > I'm seeing this on one of my old test boxes here with -rc7 + the whole tip
> > lineup.
>
> Yap, you were right about
>
>   7a8c994cbb2d ("ACPI: processor: idle: Optimize ACPI idle driver registration")
>
> having the potential of breaking something.
>
> Reverting it fixes the issue on my machine.
>
> Here's my revert log:
>
> 53f15ee83632 (HEAD -> refs/heads/rc7+) Revert "ACPI: processor: idle: Optimize ACPI idle driver registration"
> 8a2b68f3cfb5 Revert "ACPI: processor: idle: Add module import namespace"
> 8f6f9d389700 Revert "ACPI: processor: idle: Eliminate static variable flat_state_cnt"
> 09ccf5c5a51c Revert "ACPI: processor: idle: Redefine two functions as void"
> 509d71463c8c Revert "ACPI: processor: Do not expose global variable acpi_idle_driver"
> fbd0b9c0ba44 mawk fix
> 03d9f45bc0fd Merge remote-tracking branch 'tip/objtool/core' into rc7+
> 785b41beb928 Merge remote-tracking branch 'tip/master' into rc7+
> 94d77cb7e8ec Merge remote-tracking branch 'ras/edac-for-next' into rc7+

My 'fixes' branch:

git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git fixes

contains a revert of commit 53f15ee83632 along with reverts of all
cleanup commits depended on by it.

Please confirm that it works for you and I'll push it to Linus tomorrow.

Thanks!