ACK: [SRU][N][PATCH 0/1] CVE-2024-50249

[Koichiro Den]

On Mon, Jan 27, 2025 at 03:14:48PM GMT, Massimiliano Pellizzer wrote:
> [Impact]
> 
> ACPI: CPPC: Make rmw_lock a raw_spin_lock
> 
> sugov_update_shared() locks a raw_spinlock while cpc_write() locks a
> spinlock.
> 
> To have a correct wait-type order, update rmw_lock to a raw spinlock and
> ensure that interrupts will be disabled on the CPU holding it.
> 
> [Fix]
> 
> Oracular: Fixed via upstream stable updates (3273c89a8e2784)
> Noble: Clean cherry-pick from upstream
> Jammy: Fixed via upstream stable updates (7c9ca4d728f563)
> Focal: Not affected
> Bionic: Not affected
> Xenial: Not affected
> Trusty: Not affected
> 
> [Test Case]
> 
> Compile and boot tested.
> 
> [Where problems could occur]
> 
> The fix affects the CPPC driver. An issue with this fix may lead to
> instability in CPU performance scaling and power management
> functionality. A normal user might experience performance degradation,
> unexpected CPU throttling, increased power consumption, or system
> instability during high-performance workloads or when switching power
> states.
> 
> Pierre Gondois (1):
>   ACPI: CPPC: Make rmw_lock a raw_spin_lock
> 
>  drivers/acpi/cppc_acpi.c | 9 +++++----
>  include/acpi/cppc_acpi.h | 2 +-
>  2 files changed, 6 insertions(+), 5 deletions(-)
> 

Acked-by: Koichiro Den <koichiro.den at canonical.com>