| Message ID | 20240213172340.228314-1-robdclark@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/msm: Wire up tlb ops | expand |
On Tue, Feb 13, 2024 at 09:23:40AM -0800, Rob Clark wrote: > From: Rob Clark <robdclark@chromium.org> > > The brute force iommu_flush_iotlb_all() was good enough for unmap, but > in some cases a map operation could require removing a table pte entry > to replace with a block entry. This also requires tlb invalidation. > Missing this was resulting an obscure iova fault on what should be a > valid buffer address. > > Thanks to Robin Murphy for helping me understand the cause of the fault. > > Cc: Robin Murphy <robin.murphy@arm.com> > Fixes: b145c6e65eb0 ("drm/msm: Add support to create a local pagetable") Sounds like you're missing a Cc: stable@vger.kernel.org here? Or is there some reason not to backport this fix (to 5.9 and later kernels)? > Signed-off-by: Rob Clark <robdclark@chromium.org> Johan
On Wed, Feb 14, 2024 at 11:34 PM Johan Hovold <johan@kernel.org> wrote: > > On Tue, Feb 13, 2024 at 09:23:40AM -0800, Rob Clark wrote: > > From: Rob Clark <robdclark@chromium.org> > > > > The brute force iommu_flush_iotlb_all() was good enough for unmap, but > > in some cases a map operation could require removing a table pte entry > > to replace with a block entry. This also requires tlb invalidation. > > Missing this was resulting an obscure iova fault on what should be a > > valid buffer address. > > > > Thanks to Robin Murphy for helping me understand the cause of the fault. > > > > Cc: Robin Murphy <robin.murphy@arm.com> > > Fixes: b145c6e65eb0 ("drm/msm: Add support to create a local pagetable") > > Sounds like you're missing a > > Cc: stable@vger.kernel.org > > here? Or is there some reason not to backport this fix (to 5.9 and later > kernels)? No reason, I just expected the Fixes tag was sufficient BR, -R > > Signed-off-by: Rob Clark <robdclark@chromium.org> > > Johan
On Thu, Feb 15, 2024 at 07:28:53AM -0800, Rob Clark wrote: > On Wed, Feb 14, 2024 at 11:34 PM Johan Hovold <johan@kernel.org> wrote: > > > > On Tue, Feb 13, 2024 at 09:23:40AM -0800, Rob Clark wrote: > > > From: Rob Clark <robdclark@chromium.org> > > > > > > The brute force iommu_flush_iotlb_all() was good enough for unmap, but > > > in some cases a map operation could require removing a table pte entry > > > to replace with a block entry. This also requires tlb invalidation. > > > Missing this was resulting an obscure iova fault on what should be a > > > valid buffer address. > > > > > > Thanks to Robin Murphy for helping me understand the cause of the fault. > > > > > > Cc: Robin Murphy <robin.murphy@arm.com> > > > Fixes: b145c6e65eb0 ("drm/msm: Add support to create a local pagetable") > > > > Sounds like you're missing a > > > > Cc: stable@vger.kernel.org > > > > here? Or is there some reason not to backport this fix (to 5.9 and later > > kernels)? > > No reason, I just expected the Fixes tag was sufficient No, you should still mark patches intended for stable with an explicit CC-stable tag (as per the documentation). The fact that Sasha and his AI tries to catch fixes which the author and maintainer failed to tag as a fallback should not be relied upon. It also makes it harder for the stable team and others to determine what the intention with a fix was. Johan
diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c index 5cc8d358cc97..d5512037c38b 100644 --- a/drivers/gpu/drm/msm/msm_iommu.c +++ b/drivers/gpu/drm/msm/msm_iommu.c @@ -21,6 +21,8 @@ struct msm_iommu_pagetable { struct msm_mmu base; struct msm_mmu *parent; struct io_pgtable_ops *pgtbl_ops; + const struct iommu_flush_ops *tlb; + struct device *iommu_dev; unsigned long pgsize_bitmap; /* Bitmap of page sizes in use */ phys_addr_t ttbr; u32 asid; @@ -201,11 +203,33 @@ static const struct msm_mmu_funcs pagetable_funcs = { static void msm_iommu_tlb_flush_all(void *cookie) { + struct msm_iommu_pagetable *pagetable = cookie; + struct adreno_smmu_priv *adreno_smmu; + + if (!pm_runtime_get_if_in_use(pagetable->iommu_dev)) + return; + + adreno_smmu = dev_get_drvdata(pagetable->parent->dev); + + pagetable->tlb->tlb_flush_all((void *)adreno_smmu->cookie); + + pm_runtime_put_autosuspend(pagetable->iommu_dev); } static void msm_iommu_tlb_flush_walk(unsigned long iova, size_t size, size_t granule, void *cookie) { + struct msm_iommu_pagetable *pagetable = cookie; + struct adreno_smmu_priv *adreno_smmu; + + if (!pm_runtime_get_if_in_use(pagetable->iommu_dev)) + return; + + adreno_smmu = dev_get_drvdata(pagetable->parent->dev); + + pagetable->tlb->tlb_flush_walk(iova, size, granule, (void *)adreno_smmu->cookie); + + pm_runtime_put_autosuspend(pagetable->iommu_dev); } static void msm_iommu_tlb_add_page(struct iommu_iotlb_gather *gather, @@ -213,7 +237,7 @@ static void msm_iommu_tlb_add_page(struct iommu_iotlb_gather *gather, { } -static const struct iommu_flush_ops null_tlb_ops = { +static const struct iommu_flush_ops tlb_ops = { .tlb_flush_all = msm_iommu_tlb_flush_all, .tlb_flush_walk = msm_iommu_tlb_flush_walk, .tlb_add_page = msm_iommu_tlb_add_page, @@ -254,10 +278,10 @@ struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent) /* The incoming cfg will have the TTBR1 quirk enabled */ ttbr0_cfg.quirks &= ~IO_PGTABLE_QUIRK_ARM_TTBR1; - ttbr0_cfg.tlb = &null_tlb_ops; + ttbr0_cfg.tlb = &tlb_ops; pagetable->pgtbl_ops = alloc_io_pgtable_ops(ARM_64_LPAE_S1, - &ttbr0_cfg, iommu->domain); + &ttbr0_cfg, pagetable); if (!pagetable->pgtbl_ops) { kfree(pagetable); @@ -279,6 +303,8 @@ struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent) /* Needed later for TLB flush */ pagetable->parent = parent; + pagetable->tlb = ttbr1_cfg->tlb; + pagetable->iommu_dev = ttbr1_cfg->iommu_dev; pagetable->pgsize_bitmap = ttbr0_cfg.pgsize_bitmap; pagetable->ttbr = ttbr0_cfg.arm_lpae_s1_cfg.ttbr;