Re: [PATCH] powerpc/powernv/pci: Fix typo when releasing DMA resources

From: "Oliver O'Halloran" <oohall@gmail.com>
To: Frederic Barrat <fbarrat@linux.ibm.com>
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
Subject: Re: [PATCH] powerpc/powernv/pci: Fix typo when releasing DMA resources
Date: Wed, 19 Aug 2020 23:15:19 +1000	[thread overview]
Message-ID: <CAOSf1CG=ecx53ySsmX-7pK_zUJsd9LRMX5V1HBhYZBcOT2z89w@mail.gmail.com> (raw)
In-Reply-To: <20200819130741.16769-1-fbarrat@linux.ibm.com>

On Wed, Aug 19, 2020 at 11:07 PM Frederic Barrat <fbarrat@linux.ibm.com> wrote:
>
> Fix typo introduced during recent code cleanup, which could lead to
> silently not freeing resources or oops message (on PCI hotplug or CAPI
> reset).

oof

Did you actually hit that oops on CAPI reset? Including the stack
trace is helpful for avoiding this sort of problem in the future.
Anyway,

Reviewed-by: Oliver O'Halloran <oohall@gmail.com>

> Only impacts ioda2, the code path for ioda1 is correct.

yeah but no ones uses ioda1

> Fixes: 01e12629af4e ("powerpc/powernv/pci: Add explicit tracking of the DMA setup state")
> Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
> ---
>  arch/powerpc/platforms/powernv/pci-ioda.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
> index c9c25fb0783c..023a4f987bb2 100644
> --- a/arch/powerpc/platforms/powernv/pci-ioda.c
> +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
> @@ -2705,7 +2705,7 @@ void pnv_pci_ioda2_release_pe_dma(struct pnv_ioda_pe *pe)
>         struct iommu_table *tbl = pe->table_group.tables[0];
>         int64_t rc;
>
> -       if (pe->dma_setup_done)
> +       if (!pe->dma_setup_done)
>                 return;
>
>         rc = pnv_pci_ioda2_unset_window(&pe->table_group, 0);
> --
> 2.26.2
>