From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Fri, 19 Oct 2018 18:44:48 +0100 Subject: [PATCH] iommu: arm-smmu: handle client iommu translation fault handlers In-Reply-To: <6edd8f71-4363-01b6-6b45-aebc92604559@linaro.org> References: <20181010144407.23336-1-stanimir.varbanov@linaro.org> <20181010170837.GC16512@arm.com> <6edd8f71-4363-01b6-6b45-aebc92604559@linaro.org> Message-ID: <20181019174447.GB4429@brain-police> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Oct 11, 2018 at 03:26:57PM +0300, Stanimir Varbanov wrote: > On 10/10/2018 08:08 PM, Will Deacon wrote: > > On Wed, Oct 10, 2018 at 05:44:07PM +0300, Stanimir Varbanov wrote: > >> Call iommu client translation fault handler(s). > >> > >> Signed-off-by: Stanimir Varbanov > >> --- > >> drivers/iommu/arm-smmu.c | 3 +++ > >> 1 file changed, 3 insertions(+) > >> > >> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > >> index 066f4c8daf4e..02a8aab0cc59 100644 > >> --- a/drivers/iommu/arm-smmu.c > >> +++ b/drivers/iommu/arm-smmu.c > >> @@ -568,6 +568,9 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev) > >> fsr, iova, fsynr, cfg->cbndx); > >> > >> writel(fsr, cb_base + ARM_SMMU_CB_FSR); > >> + > >> + report_iommu_fault(domain, smmu->dev, iova, 0); > > > > Who's using this? Generally, the callback here isn't so useful because it's > > The idea was to use it from video driver to dump few multimedia > interconnect registers which will give us some more info about the fault. > > > called in irq context. We also don't enable stalling since 3714ce1d6655. > > > > We previously had fairly detailed discussions on the list with Rob Clark > > about alternative ways to design this, but I don't remember where it ended > > up. > > It will be useful if you point me to the discussion. Thanks! There's more, but some stuff I managed to dig up is here: https://lists.linuxfoundation.org/pipermail/iommu/2017-January/019931.html https://lists.linuxfoundation.org/pipermail/iommu/2017-September/024143.html Will