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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ZvoI9cDNeMQ/QUGRaeRBxYR4fmI11pv0SGBjJfNmJBwvMwbksmgTbDIfIGsO?= =?us-ascii?Q?YkG19pJ20WKt49qpW+X4QrzhauIp3AENl2V903yf3ac7qWwdlO2o/xlfvZBK?= =?us-ascii?Q?6Xy2CzFHKmsVUMkSrFLHbrazZS5QVGMBfBYY+1mjGD36Gn4e67XfzhP0c+Xq?= =?us-ascii?Q?ETiUmUdMuxYddFPvbCkztKPRhM+c+5swGrMEe/JXys6V/PydG9RNL9Kz95d9?= =?us-ascii?Q?27LN1sGeQ76hG6BkNIdf/tqqJybxQ1zoRyXbp5VuvoYq4uq+pELw8ariblmT?= =?us-ascii?Q?xpO+hvp1QsQFuQLU/eDWZ2m6E9KEF9Wsdm42eh28KMCeD37YjEG6Km7sjZRk?= =?us-ascii?Q?rUWdKLuXfyctpFBPfAByx1+cCw/PQIQKZ7VNJcTHNlvKqd8Du7nLQAMJGtoY?= =?us-ascii?Q?juMjBwFk+VbBxoh1pxUWcPQD6Bb9mGAHvU/0w1SBbnQc4R3hGKYlxmiV2wVk?= =?us-ascii?Q?2yldBIGt6umo8jpsjZUzfKrZIqg8G5oHt9xXBgI5JRW4r4fShEQDu687zowS?= =?us-ascii?Q?sW9QyAuQN9cYUYNdE6viISbQ7natjXsak4XQiSMwgmxAtOo+5S0teUPsVRnp?= =?us-ascii?Q?Uc7GiOTu6RVRALZ9hjQSSobYP0Zs4iv1d/4mfPVI4/Fj2Rnl0gLGL0FxDaR/?= =?us-ascii?Q?2TlnlNiQEqeRDx8qtR5+fYJhMTiVrX6WR1HKWaU8z9GEqzrELVfd3oHSvQae?= =?us-ascii?Q?Q6ACV4lparuwcumSH3396spTAEfhbb9hJoM7o8bttny/Ws6+6uoYWDy8GSfU?= =?us-ascii?Q?ZSRiCm6WFBINZCqbcqY4zFNpIJBGnu9bkbdiTdht6kDuZpwvpa8UdCvDu3DJ?= =?us-ascii?Q?ijRASVG2YY3H7rMI0/i8m/yOXV2lLJeYvFwXEhtuk8CLdjxjoIv+yqCIy8dk?= =?us-ascii?Q?2BcnfLF3AIKTS1xleWAVyPsGH2Fd5eel1JJixXPItSQa6S1fn5xUOPVPX2yN?= =?us-ascii?Q?fweStH6zUf3O4ESfRTkPgcbe5HJC8xpxbQLj+Aa2/P0N7itIgHvqmScWJJ42?= =?us-ascii?Q?0K3l8YrcljJOaMg2p9bx+sZmaLLwe9SYJTs8X9qwV0DwoVzGudNzhUoz2R3+?= =?us-ascii?Q?oJaq+K/HJwZ3rAevDpOaUQ1DL/8416YI2YpHOqGk3AF8EB3m4IrShTEL+04h?= =?us-ascii?Q?roKHLyM+so3xxLttHGcha6RbjEB4fR/dm0xgOLlOvCKMFijHdE6jLGd86/pT?= =?us-ascii?Q?efTXeYaFS3Hn9WtpVQPhRTKAFLSh2vkqQ0eF82jAJ5dW8UxekCQC3O7/crLQ?= =?us-ascii?Q?4aw8ldMgIUQuIIuXr0hKk2PqKO+sNJOu3OjTHOXKReI5dli3Ra+U8Zo/wEct?= =?us-ascii?Q?3GxsSSaIwoz766e/EvtlleXUvILd9cRiM/oHkdrQ4aTgYZBw/ohH3jkwALkz?= =?us-ascii?Q?vr0tmuLUbuI9cEQE534iEkbGvgonoZCIXhkAx049Mg06vT9MyaxceDZV+v/a?= =?us-ascii?Q?mYuh5g4PAvvTJqVgKPFVClYNXfABe+uHhpQOIEGBETjj/BMKzmeiCPqiI2b+?= =?us-ascii?Q?j5kftKtdcoWm1CcIqPsGrL+Uk82VRL+uN0hHi5TBF6tZNFGk2vj1knyG0sJm?= =?us-ascii?Q?x3RlY3ob4ghs33J3Mf2wD46YTMmxMavDaP1uy0RXKRCWMXkWGNqK7S53DP18?= =?us-ascii?Q?eEtJP88FK3LYkS+CzBPFUmqTphXasxlH8CYB2IsqZUqGXW5leB+pAasCS8Zu?= =?us-ascii?Q?oJW48nU0bi2cyUltUNs7Y+QlHqJQlFq/d5ECrswIwBDPONRy?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a95a48c6-2019-4bcb-186a-08deb5ce562b X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 May 2026 17:44:54.9029 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: DWY/DLN6yAwH1Abj1pOIpiyI0uM3KD3CuUETOv2Y8MRXZHkPGg3tjyx4FdQ+yEAK X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PPFD7DCFAC03 On Sun, May 10, 2026 at 02:23:02PM -0700, Nicolin Chen wrote: > In kdump cases, the crashed kernel's CDs and page tables can be corrupted, > which could trigger event spamming. Also, we cannot serve page requests. > > Skip the IRQ setup for EVTQ/PRIQ in arm_smmu_setup_irqs(), and guard the > thread functions against being entered via a combined-IRQ delivery while > the queue is disabled. > > Fixes: b63b3439b856 ("iommu/arm-smmu-v3: Abort all transactions if SMMU is enabled in kdump kernel") > Cc: stable@vger.kernel.org # v6.12+ > Reviewed-by: Kevin Tian > Signed-off-by: Nicolin Chen > --- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 23 +++++++++++++++++++-- > 1 file changed, 21 insertions(+), 2 deletions(-) > > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > index 579c8af82d6b6..ebb0826d74541 100644 > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > @@ -2364,6 +2364,14 @@ static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev) > static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL, > DEFAULT_RATELIMIT_BURST); > > + /* > + * A combined IRQ might call into this function with the queue disabled. > + * E.g. kdump, where stale HW PROD vs SW CONS would drive a bogus drain > + * and a CONS write to a disabled queue. > + */ > + if (!(readl_relaxed(smmu->base + ARM_SMMU_CR0) & CR0_EVTQEN)) > + return IRQ_NONE; I don't think we should be doing register reads on these paths. Why not load a different irq function instead? Jason