6.15-stable review patch. If anyone has any objections, please let me know.
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From: Junxiao Chang junxiao.chang@intel.com
[ Upstream commit 8cadce97bf264ed478669c6f32d5603b34608335 ]
MEI GSC interrupt comes from i915. It has top half and bottom half. Top half is called from i915 interrupt handler. It should be in irq disabled context.
With RT kernel, by default i915 IRQ handler is in threaded IRQ. MEI GSC top half might be in threaded IRQ context. generic_handle_irq_safe API could be called from either IRQ or process context, it disables local IRQ then calls MEI GSC interrupt top half.
This change fixes A380/A770 GPU boot hang issue with RT kernel.
Fixes: 1e3dc1d8622b ("drm/i915/gsc: add gsc as a mei auxiliary device") Tested-by: Furong Zhou furong.zhou@intel.com Suggested-by: Sebastian Andrzej Siewior bigeasy@linutronix.de Acked-by: Sebastian Andrzej Siewior bigeasy@linutronix.de Signed-off-by: Junxiao Chang junxiao.chang@intel.com Link: https://lore.kernel.org/r/20250425151108.643649-1-junxiao.chang@intel.com Reviewed-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com (cherry picked from commit dccf655f69002d496a527ba441b4f008aa5bebbf) Signed-off-by: Joonas Lahtinen joonas.lahtinen@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/i915/gt/intel_gsc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_gsc.c b/drivers/gpu/drm/i915/gt/intel_gsc.c index 1e925c75fb080..c43febc862dc3 100644 --- a/drivers/gpu/drm/i915/gt/intel_gsc.c +++ b/drivers/gpu/drm/i915/gt/intel_gsc.c @@ -284,7 +284,7 @@ static void gsc_irq_handler(struct intel_gt *gt, unsigned int intf_id) if (gt->gsc.intf[intf_id].irq < 0) return;
- ret = generic_handle_irq(gt->gsc.intf[intf_id].irq); + ret = generic_handle_irq_safe(gt->gsc.intf[intf_id].irq); if (ret) gt_err_ratelimited(gt, "error handling GSC irq: %d\n", ret); }