On Tue, 27 Dec 2022 20:36:08 +0000,
Sasha Levin <sashal@xxxxxxxxxx> wrote:
>
> From: Marc Zyngier <maz@xxxxxxxxxx>
>
> [ Upstream commit 4545c6a3d6ba71747eaa984c338ddd745e56e23f ]
>
> Since 2f2940d16823 ("genirq/msi: Remove filter from
> msi_free_descs_free_range()"), the core MSI code relies on the
> msi_desc->irq field to have been cleared before the descriptor
> can be freed, as it indicates that there is no association with
> a device anymore.
>
> The irq domain code provides this guarantee, and so does s390,
> which is one of the two architectures not using irq domains for
> MSIs.
>
> Powerpc, however, is missing this particular requirements,
> leading in a splat and leaked MSI descriptors.
>
> Adding the now required irq reset to the handful of powerpc backends
> that implement MSIs fixes that particular problem.
>
> Reported-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
> Link: https://lore.kernel.org/r/70dab88e-6119-0c12-7c6a-61bcbe239f66@xxxxxxxxxxxx
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> arch/powerpc/platforms/4xx/hsta_msi.c | 1 +
> arch/powerpc/platforms/cell/axon_msi.c | 1 +
> arch/powerpc/platforms/pasemi/msi.c | 1 +
> arch/powerpc/sysdev/fsl_msi.c | 1 +
> arch/powerpc/sysdev/mpic_u3msi.c | 1 +
> 5 files changed, 5 insertions(+)
Please drop this patch from all stable branches. It isn't needed
before 6.2, and doesn't fix anything on its own as nobody uses this
structure after this point.
M.
--
Without deviation from the norm, progress is not possible.
