From 4bbc16a353a98023e5ddfca7c1fc0e49971cf4d0 Mon Sep 17 00:00:00 2001 From: Rosen Penev Date: Sun, 12 Jul 2026 14:37:26 -0700 Subject: [PATCH 1/4] ata: sata_dwc_460ex: enable SATA interrupts only after IRQ handler is registered sata_dwc_enable_interrupts() is called before platform_get_irq() and ata_host_activate(), leaving the SATA controller's interrupt mask enabled without a registered handler. If a later step fails (irq request, phy init, etc.) or if the controller asserts an interrupt during probe, the irq line may fire with no handler, causing a spurious interrupt storm. Move sata_dwc_enable_interrupts() after ata_host_activate() so that interrupts are only unmasked once the handler is registered and the core is fully initialized. Fixes: 62936009f35a ("[libata] Add 460EX on-chip SATA driver, sata_dwc_460ex") Assisted-by: opencode:big-pickle Signed-off-by: Rosen Penev Signed-off-by: Damien Le Moal --- drivers/ata/sata_dwc_460ex.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c index 4fc22ce4bd9a..e10eeb8ca030 100644 --- a/drivers/ata/sata_dwc_460ex.c +++ b/drivers/ata/sata_dwc_460ex.c @@ -1169,9 +1169,6 @@ static int sata_dwc_probe(struct platform_device *ofdev) /* Save dev for later use in dev_xxx() routines */ hsdev->dev = dev; - /* Enable SATA Interrupts */ - sata_dwc_enable_interrupts(hsdev); - /* Get SATA interrupt number */ irq = irq_of_parse_and_map(np, 0); if (!irq) { @@ -1204,6 +1201,8 @@ static int sata_dwc_probe(struct platform_device *ofdev) if (err) dev_err(dev, "failed to activate host"); + /* Enable SATA Interrupts */ + sata_dwc_enable_interrupts(hsdev); return 0; error_out: From a4af122106f73ea510bb35a9ea1dedd980fc0db7 Mon Sep 17 00:00:00 2001 From: Rosen Penev Date: Sun, 12 Jul 2026 14:37:25 -0700 Subject: [PATCH 2/4] ata: sata_dwc_460ex: use platform_get_irq() Replace irq_of_parse_and_map() with platform_get_irq() in both sata_dwc_dma_init_old() and sata_dwc_probe(). This is the preferred way to obtain IRQs for platform devices and provides better error reporting. Remove the now-unnecessary #include . irq_of_parse_and_map() requires irq_dispose_mapping(), which is missing. Also fix unused variable when CONFIG_SATA_DWC_OLD_DMA is disabled. Fixes: 62936009f35a ("[libata] Add 460EX on-chip SATA driver, sata_dwc_460ex") Assisted-by: opencode:big-pickle Signed-off-by: Rosen Penev Signed-off-by: Damien Le Moal --- drivers/ata/sata_dwc_460ex.c | 21 +++++++-------------- 1 file changed, 7 insertions(+), 14 deletions(-) diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c index e10eeb8ca030..85c5e67e9175 100644 --- a/drivers/ata/sata_dwc_460ex.c +++ b/drivers/ata/sata_dwc_460ex.c @@ -19,7 +19,6 @@ #include #include #include -#include #include #include #include @@ -226,7 +225,6 @@ static int sata_dwc_dma_init_old(struct platform_device *pdev, struct sata_dwc_device *hsdev) { struct device *dev = &pdev->dev; - struct device_node *np = dev->of_node; hsdev->dma = devm_kzalloc(dev, sizeof(*hsdev->dma), GFP_KERNEL); if (!hsdev->dma) @@ -236,11 +234,9 @@ static int sata_dwc_dma_init_old(struct platform_device *pdev, hsdev->dma->id = pdev->id; /* Get SATA DMA interrupt number */ - hsdev->dma->irq = irq_of_parse_and_map(np, 1); - if (!hsdev->dma->irq) { - dev_err(dev, "no SATA DMA irq\n"); - return -ENODEV; - } + hsdev->dma->irq = platform_get_irq(pdev, 1); + if (hsdev->dma->irq < 0) + return hsdev->dma->irq; /* Get physical SATA DMA register base address */ hsdev->dma->regs = devm_platform_ioremap_resource(pdev, 1); @@ -1126,7 +1122,6 @@ static const struct ata_port_info sata_dwc_port_info[] = { static int sata_dwc_probe(struct platform_device *ofdev) { struct device *dev = &ofdev->dev; - struct device_node *np = dev->of_node; struct sata_dwc_device *hsdev; u32 idr, versionr; char *ver = (char *)&versionr; @@ -1170,14 +1165,12 @@ static int sata_dwc_probe(struct platform_device *ofdev) hsdev->dev = dev; /* Get SATA interrupt number */ - irq = irq_of_parse_and_map(np, 0); - if (!irq) { - dev_err(dev, "no SATA DMA irq\n"); - return -ENODEV; - } + irq = platform_get_irq(ofdev, 0); + if (irq < 0) + return irq; #ifdef CONFIG_SATA_DWC_OLD_DMA - if (!of_property_present(np, "dmas")) { + if (!of_property_present(dev->of_node, "dmas")) { err = sata_dwc_dma_init_old(ofdev, hsdev); if (err) return err; From 66c4e310ad71f41e41736d33dd8a1fb5eaaec7f3 Mon Sep 17 00:00:00 2001 From: Rosen Penev Date: Sun, 12 Jul 2026 14:37:27 -0700 Subject: [PATCH 3/4] ata: sata_dwc_460ex: fix clear_interrupt_bit() clearing all pending interrupts clear_interrupt_bit() ignores the bit argument and performs a read-write-back of the entire INTPR register. If INTPR uses standard Write-1-to-Clear semantics, this clears every pending interrupt bit, not just the intended one. Coalesced interrupts (e.g. DMAT + NEWFP) would be cleared together, silently losing the second event. Write only the specific bit to clear so that other pending interrupts are preserved. Fixes: 62936009f35a ("[libata] Add 460EX on-chip SATA driver, sata_dwc_460ex") Assisted-by: opencode:big-pickle Signed-off-by: Rosen Penev Signed-off-by: Damien Le Moal --- drivers/ata/sata_dwc_460ex.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c index 85c5e67e9175..bc543a408963 100644 --- a/drivers/ata/sata_dwc_460ex.c +++ b/drivers/ata/sata_dwc_460ex.c @@ -394,8 +394,7 @@ static void clear_serror(struct ata_port *ap) static void clear_interrupt_bit(struct sata_dwc_device *hsdev, u32 bit) { - sata_dwc_writel(&hsdev->sata_dwc_regs->intpr, - sata_dwc_readl(&hsdev->sata_dwc_regs->intpr)); + sata_dwc_writel(&hsdev->sata_dwc_regs->intpr, bit); } static u32 qcmd_tag_to_mask(u8 tag) From c2130f6553f4a5cbdc259de069600117a995f197 Mon Sep 17 00:00:00 2001 From: Rosen Penev Date: Sun, 12 Jul 2026 14:37:28 -0700 Subject: [PATCH 4/4] ata: sata_dwc_460ex: fix infinite loop in NCQ tag completion bit-scanning The hand-rolled bit-scanning loop in the NCQ completion path has an infinite loop bug. When tag_mask has only high bits set (e.g. 0x80000000), the inner while loop left-shifts tag_mask until it overflows to 0. At that point !(0 & 1) is always true and 0 <<= 1 stays 0, causing an infinite loop in hardirq context with a spinlock held. Replace the open-coded bit-scanning with __ffs() which correctly finds the least significant set bit and is bounded by the width of the argument. Fixes: 62936009f35a ("[libata] Add 460EX on-chip SATA driver, sata_dwc_460ex") Assisted-by: opencode:big-pickle Signed-off-by: Rosen Penev Signed-off-by: Damien Le Moal --- drivers/ata/sata_dwc_460ex.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c index bc543a408963..8e3fc713891a 100644 --- a/drivers/ata/sata_dwc_460ex.c +++ b/drivers/ata/sata_dwc_460ex.c @@ -607,14 +607,9 @@ static irqreturn_t sata_dwc_isr(int irq, void *dev_instance) status = ap->ops->sff_check_status(ap); dev_dbg(ap->dev, "%s ATA status register=0x%x\n", __func__, status); - tag = 0; while (tag_mask) { - while (!(tag_mask & 0x00000001)) { - tag++; - tag_mask <<= 1; - } - - tag_mask &= (~0x00000001); + tag = __ffs(tag_mask); + tag_mask &= ~(1U << tag); qc = ata_qc_from_tag(ap, tag); if (unlikely(!qc)) { dev_err(ap->dev, "failed to get qc");