This is a note to let you know that I've just added the patch titled
iommu/tegra241-cmdqv: Fix alignment failure at max_n_shift
to the 6.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
iommu-tegra241-cmdqv-fix-alignment-failure-at-max_n_.patch
and it can be found in the queue-6.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 439e0748ea1ff5b892d4c7101e8483465650f4fa
Author: Nicolin Chen <nicolinc@xxxxxxxxxx>
Date: Sun Nov 10 19:02:26 2024 -0800
iommu/tegra241-cmdqv: Fix alignment failure at max_n_shift
[ Upstream commit a3799717b881aa0f4e722afb70e7b8ba84ae4f36 ]
When configuring a kernel with PAGE_SIZE=4KB, depending on its setting of
CONFIG_CMA_ALIGNMENT, VCMDQ_LOG2SIZE_MAX=19 could fail the alignment test
and trigger a WARN_ON:
WARNING: at drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:3646
Call trace:
arm_smmu_init_one_queue+0x15c/0x210
tegra241_cmdqv_init_structures+0x114/0x338
arm_smmu_device_probe+0xb48/0x1d90
Fix it by capping max_n_shift to CMDQ_MAX_SZ_SHIFT as SMMUv3 CMDQ does.
Fixes: 918eb5c856f6 ("iommu/arm-smmu-v3: Add in-kernel support for NVIDIA Tegra241 (Grace) CMDQV")
Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20241111030226.1940737-1-nicolinc@xxxxxxxxxx
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
index a243c543598ce..6b479592140c4 100644
--- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
+++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
@@ -509,7 +509,8 @@ static int tegra241_vcmdq_alloc_smmu_cmdq(struct tegra241_vcmdq *vcmdq)
snprintf(name, 16, "vcmdq%u", vcmdq->idx);
- q->llq.max_n_shift = VCMDQ_LOG2SIZE_MAX;
+ /* Queue size, capped to ensure natural alignment */
+ q->llq.max_n_shift = min_t(u32, CMDQ_MAX_SZ_SHIFT, VCMDQ_LOG2SIZE_MAX);
/* Use the common helper to init the VCMDQ, and then... */
ret = arm_smmu_init_one_queue(smmu, q, vcmdq->page0,
