6.6-stable review patch. If anyone has any objections, please let me know.
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From: Devarsh Thakkar devarsht@ti.com
[ Upstream commit a9a73f2661e6f625d306c9b0ef082e4593f45a21 ]
The driver has a spinlock for protecting the irq_masks field and irq enable registers. However, the driver misses protecting the irq status registers which can lead to races.
Take the spinlock when accessing irqstatus too.
Fixes: 32a1795f57ee ("drm/tidss: New driver for TI Keystone platform Display SubSystem") Cc: stable@vger.kernel.org Signed-off-by: Devarsh Thakkar devarsht@ti.com [Tomi: updated the desc] Reviewed-by: Jonathan Cormier jcormier@criticallink.com Tested-by: Jonathan Cormier jcormier@criticallink.com Reviewed-by: Aradhya Bhatia aradhya.bhatia@linux.dev Signed-off-by: Tomi Valkeinen tomi.valkeinen@ideasonboard.com Link: https://patchwork.freedesktop.org/patch/msgid/20241021-tidss-irq-fix-v1-6-82... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/tidss/tidss_dispc.c | 4 ++++ drivers/gpu/drm/tidss/tidss_irq.c | 2 ++ 2 files changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c index 4327e1203c565..355c64bafb82b 100644 --- a/drivers/gpu/drm/tidss/tidss_dispc.c +++ b/drivers/gpu/drm/tidss/tidss_dispc.c @@ -2710,8 +2710,12 @@ static void dispc_init_errata(struct dispc_device *dispc) */ static void dispc_softreset_k2g(struct dispc_device *dispc) { + unsigned long flags; + + spin_lock_irqsave(&dispc->tidss->wait_lock, flags); dispc_set_irqenable(dispc, 0); dispc_read_and_clear_irqstatus(dispc); + spin_unlock_irqrestore(&dispc->tidss->wait_lock, flags);
for (unsigned int vp_idx = 0; vp_idx < dispc->feat->num_vps; ++vp_idx) VP_REG_FLD_MOD(dispc, vp_idx, DISPC_VP_CONTROL, 0, 0, 0); diff --git a/drivers/gpu/drm/tidss/tidss_irq.c b/drivers/gpu/drm/tidss/tidss_irq.c index 0c681c7600bcb..f13c7e434f8ed 100644 --- a/drivers/gpu/drm/tidss/tidss_irq.c +++ b/drivers/gpu/drm/tidss/tidss_irq.c @@ -60,7 +60,9 @@ static irqreturn_t tidss_irq_handler(int irq, void *arg) unsigned int id; dispc_irq_t irqstatus;
+ spin_lock(&tidss->wait_lock); irqstatus = dispc_read_and_clear_irqstatus(tidss->dispc); + spin_unlock(&tidss->wait_lock);
for (id = 0; id < tidss->num_crtcs; id++) { struct drm_crtc *crtc = tidss->crtcs[id];