Hi folks,

Three fixes to the GICv3 and ITS drivers, from reviewing the GIC series
floating around and chasing down Sashiko's reports.

The first releases the partition node that gic_irq_get_fwspec_info()
takes from of_find_node_by_phandle() and never puts. Sashiko raised it
on an of/irq patch of mine, and I said a fix was forthcoming [1].

The second widens the per-device MSI clamp, which truncates to zero when
GITS_TYPER.ID_bits is at its maximum and then denies every MSI on that
ITS. I couldn't find an implementation that reports that maximum, so
this is one value at the edge rather than something anyone is hitting.
It carries Cc: stable because the commit it fixes was itself
backported, so drop the tag if you'd rather.

The third clears vpt_page once its_vpe_teardown() has freed it, so the
NULL guard holds if teardown runs again on the same vPE.

Based on Linux 7.3-rc2 (df2908090cda3).

Cheers,
/fuad

[1] https://lore.kernel.org/all/CA+EHjTx7eP_30vP47=UFk_wMAut-2uf+2DF-MZqn2SLE_k-8qg@mail.gmail.com/

Fuad Tabba (3):
  irqchip/gic-v3: Release the partition node in
    gic_irq_get_fwspec_info()
  irqchip/gic-v3-its: Don't clamp nvecs to zero when id_bits is 32
  irqchip/gic-v3-its: Clear vpt_page after freeing the pending table

 drivers/irqchip/irq-gic-v3-its.c | 3 ++-
 drivers/irqchip/irq-gic-v3.c     | 7 ++++---
 2 files changed, 6 insertions(+), 4 deletions(-)


base-commit: df2908090cda368b01ff43709f51890076c56157
-- 
2.39.5

Hi Fuad,

On 9/8/26 10:26 PM, Fuad Tabba wrote:
> Hi folks,
> 
> Three fixes to the GICv3 and ITS drivers, from reviewing the GIC series
> floating around and chasing down Sashiko's reports.
> 
> The first releases the partition node that gic_irq_get_fwspec_info()
> takes from of_find_node_by_phandle() and never puts. Sashiko raised it
> on an of/irq patch of mine, and I said a fix was forthcoming [1].
> 
> The second widens the per-device MSI clamp, which truncates to zero when
> GITS_TYPER.ID_bits is at its maximum and then denies every MSI on that
> ITS. I couldn't find an implementation that reports that maximum, so
> this is one value at the edge rather than something anyone is hitting.
> It carries Cc: stable because the commit it fixes was itself
> backported, so drop the tag if you'd rather.
> 
> The third clears vpt_page once its_vpe_teardown() has freed it, so the
> NULL guard holds if teardown runs again on the same vPE.
> 
> Based on Linux 7.3-rc2 (df2908090cda3).
> 
> Cheers,
> /fuad
> 
> [1] https://lore.kernel.org/all/CA+EHjTx7eP_30vP47=UFk_wMAut-2uf+2DF-MZqn2SLE_k-8qg@mail.gmail.com/
> 
> Fuad Tabba (3):
>   irqchip/gic-v3: Release the partition node in
>     gic_irq_get_fwspec_info()
>   irqchip/gic-v3-its: Don't clamp nvecs to zero when id_bits is 32
>   irqchip/gic-v3-its: Clear vpt_page after freeing the pending table
> 
>  drivers/irqchip/irq-gic-v3-its.c | 3 ++-
>  drivers/irqchip/irq-gic-v3.c     | 7 ++++---
>  2 files changed, 6 insertions(+), 4 deletions(-)

All look good to me.  Thanks for the fixes!

Reviewed-by: Zenghui Yu (Huawei) <zenghui.yu@linux.dev>

Zenghui

On Tue, 2026-09-08 at 15:26 +0100, Fuad Tabba wrote:
> Hi folks,
> 
> Three fixes to the GICv3 and ITS drivers, from reviewing the GIC series
> floating around and chasing down Sashiko's reports.
> 
> The first releases the partition node that gic_irq_get_fwspec_info()
> takes from of_find_node_by_phandle() and never puts. Sashiko raised it
> on an of/irq patch of mine, and I said a fix was forthcoming [1].
> 
> The second widens the per-device MSI clamp, which truncates to zero when
> GITS_TYPER.ID_bits is at its maximum and then denies every MSI on that
> ITS. I couldn't find an implementation that reports that maximum, so
> this is one value at the edge rather than something anyone is hitting.
> It carries Cc: stable because the commit it fixes was itself
> backported, so drop the tag if you'd rather.
> 
> The third clears vpt_page once its_vpe_teardown() has freed it, so the
> NULL guard holds if teardown runs again on the same vPE.
> 
> Based on Linux 7.3-rc2 (df2908090cda3).
> 
> Cheers,
> /fuad
> 
> [1] https://lore.kernel.org/all/CA+EHjTx7eP_30vP47=UFk_wMAut-2uf+2DF-MZqn2SLE_k-8qg@mail.gmail.com/
> 
> Fuad Tabba (3):
>   irqchip/gic-v3: Release the partition node in
>     gic_irq_get_fwspec_info()
>   irqchip/gic-v3-its: Don't clamp nvecs to zero when id_bits is 32
>   irqchip/gic-v3-its: Clear vpt_page after freeing the pending table
> 
>  drivers/irqchip/irq-gic-v3-its.c | 3 ++-
>  drivers/irqchip/irq-gic-v3.c     | 7 ++++---
>  2 files changed, 6 insertions(+), 4 deletions(-)
> 
> 
> base-commit: df2908090cda368b01ff43709f51890076c56157

Reviewed-by: Radu Rendec <radu@rendec.net>

On Tue, 08 Sep 2026 15:26:29 +0100,
Fuad Tabba <fuad.tabba@linux.dev> wrote:
> 
> Hi folks,
> 
> Three fixes to the GICv3 and ITS drivers, from reviewing the GIC series
> floating around and chasing down Sashiko's reports.
> 
> The first releases the partition node that gic_irq_get_fwspec_info()
> takes from of_find_node_by_phandle() and never puts. Sashiko raised it
> on an of/irq patch of mine, and I said a fix was forthcoming [1].
> 
> The second widens the per-device MSI clamp, which truncates to zero when
> GITS_TYPER.ID_bits is at its maximum and then denies every MSI on that
> ITS. I couldn't find an implementation that reports that maximum, so
> this is one value at the edge rather than something anyone is hitting.
> It carries Cc: stable because the commit it fixes was itself
> backported, so drop the tag if you'd rather.
> 
> The third clears vpt_page once its_vpe_teardown() has freed it, so the
> NULL guard holds if teardown runs again on the same vPE.
> 
> Based on Linux 7.3-rc2 (df2908090cda3).

Reviewed-by: Marc Zyngier <maz@kernel.org>

	M.

-- 
Without deviation from the norm, progress is not possible.