[PATCH v6 10/17] iommu/arm-smmu-v3: Recheck CMDQ_ERR in tegra241_vintf0_handle_error()
COOLING6d
From: Nicolin Chen <hidden>
Date: 2026-09-23 20:12:38
Also in:
linux-acpi, linux-cxl, linux-iommu, linux-pci, lkml
Subsystem:
arm smmu drivers, iommu subsystem, tegra iommu drivers, the rest · Maintainers:
Will Deacon, Joerg Roedel, Thierry Reding, Linus Torvalds
Revision v6 of 4 in this series.
Revisions (4)
- v3 [diff vs current]
- v4 [diff vs current]
- v5 [diff vs current]
- v6 current
A subsequent change will allow cmdq_err_handler to ack a pending CMDQ_ERR concurrently with tegra241_vintf0_handle_error(). Take cmdq_err_lock around the gerror read and ack, and recheck (gerror ^ gerrorn) & GERROR_CMDQ_ERR before calling __arm_smmu_cmdq_skip_err() so a concurrent ack doesn't cause us to skip_err on an already-handled error. arm_smmu_gerror_handler() already covers this via its existing early-exit on no-active-bits. tegra241_vcmdq_hw_deinit() acks the same GERROR/GERRORN pair unlocked, and the error IRQ is live from probe, so a latched-error ISR can race a VCMDQ deinit during a device reset. Take the lock around that ack as well. Since a user-owned VCMDQ never goes through arm_smmu_cmdq_init() yet does reach tegra241_vcmdq_hw_deinit(), initialize its cmdq_err_lock at allocation. Signed-off-by: Nicolin Chen <redacted> --- drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
index a595769e7ecd6..cf008bee213c4 100644
--- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
+++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c@@ -323,7 +323,8 @@ static void tegra241_vintf0_handle_error(struct tegra241_vintf *vintf) unsigned long map_bit = __ffs64(map); unsigned long lidx = 64 * i + map_bit; struct tegra241_vcmdq *vcmdq; - u32 gerror; + unsigned long flags; + u32 gerror, gerrorn; map &= ~BIT_ULL(map_bit);
@@ -335,9 +336,16 @@ static void tegra241_vintf0_handle_error(struct tegra241_vintf *vintf) if (!vcmdq) continue; + raw_spin_lock_irqsave(&vcmdq->cmdq.cmdq_err_lock, flags); gerror = readl_relaxed(REG_VCMDQ_PAGE0(vcmdq, GERROR)); - __arm_smmu_cmdq_skip_err(&cmdqv->smmu, &vcmdq->cmdq); + gerrorn = readl_relaxed(REG_VCMDQ_PAGE0(vcmdq, GERRORN)); + + if ((gerror ^ gerrorn) & GERROR_CMDQ_ERR) + __arm_smmu_cmdq_skip_err(&cmdqv->smmu, + &vcmdq->cmdq); writel(gerror, REG_VCMDQ_PAGE0(vcmdq, GERRORN)); + raw_spin_unlock_irqrestore(&vcmdq->cmdq.cmdq_err_lock, + flags); } } }
@@ -477,6 +485,7 @@ static void tegra241_vcmdq_hw_deinit(struct tegra241_vcmdq *vcmdq) { char header[64], *h = lvcmdq_error_header(vcmdq, header, 64); u32 gerrorn, gerror; + unsigned long flags; if (vcmdq_write_config(vcmdq, 0)) { dev_err(vcmdq->cmdqv->dev,
@@ -492,6 +501,7 @@ static void tegra241_vcmdq_hw_deinit(struct tegra241_vcmdq *vcmdq) writeq_relaxed(0, REG_VCMDQ_PAGE1(vcmdq, BASE)); writeq_relaxed(0, REG_VCMDQ_PAGE1(vcmdq, CONS_INDX_BASE)); + raw_spin_lock_irqsave(&vcmdq->cmdq.cmdq_err_lock, flags); gerrorn = readl_relaxed(REG_VCMDQ_PAGE0(vcmdq, GERRORN)); gerror = readl_relaxed(REG_VCMDQ_PAGE0(vcmdq, GERROR)); if (gerror != gerrorn) {
@@ -499,6 +509,7 @@ static void tegra241_vcmdq_hw_deinit(struct tegra241_vcmdq *vcmdq) "%suncleared error detected, resetting\n", h); writel(gerror, REG_VCMDQ_PAGE0(vcmdq, GERRORN)); } + raw_spin_unlock_irqrestore(&vcmdq->cmdq.cmdq_err_lock, flags); dev_dbg(vcmdq->cmdqv->dev, "%sdeinited\n", h); }
@@ -1206,6 +1217,8 @@ static int tegra241_vintf_alloc_lvcmdq_user(struct iommufd_hw_queue *hw_queue, vcmdq->cmdq.q.q_base = base_addr_pa & VCMDQ_ADDR; vcmdq->cmdq.q.q_base |= log2size; + raw_spin_lock_init(&vcmdq->cmdq.cmdq_err_lock); + ret = tegra241_vcmdq_hw_init_user(vcmdq); if (ret) goto unmap_lvcmdq;
--
2.43.0