This is a note to let you know that I've just added the patch titled
drm/panfrost: Clear MMU irqs before handling the fault
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-panfrost-clear-mmu-irqs-before-handling-the-fault.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 3aa0a80fc692c9959c261f4c5bfe9c23ddd90562 Mon Sep 17 00:00:00 2001
From: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
Date: Fri, 5 Feb 2021 12:17:55 +0100
Subject: drm/panfrost: Clear MMU irqs before handling the fault
From: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
commit 3aa0a80fc692c9959c261f4c5bfe9c23ddd90562 upstream.
When a fault is handled it will unblock the GPU which will continue
executing its shader and might fault almost immediately on a different
page. If we clear interrupts after handling the fault we might miss new
faults, so clear them before.
Cc: <stable@xxxxxxxxxxxxxxx>
Fixes: 187d2929206e ("drm/panfrost: Add support for GPU heap allocations")
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
Reviewed-by: Steven Price <steven.price@xxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20210205111757.585248-2-boris.brezillon@xxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/panfrost/panfrost_mmu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
@@ -600,6 +600,8 @@ static irqreturn_t panfrost_mmu_irq_hand
access_type = (fault_status >> 8) & 0x3;
source_id = (fault_status >> 16);
+ mmu_write(pfdev, MMU_INT_CLEAR, mask);
+
/* Page fault only */
ret = -1;
if ((status & mask) == BIT(i) && (exception_type & 0xF8) == 0xC0)
@@ -623,8 +625,6 @@ static irqreturn_t panfrost_mmu_irq_hand
access_type, access_type_name(pfdev, fault_status),
source_id);
- mmu_write(pfdev, MMU_INT_CLEAR, mask);
-
status &= ~mask;
}
Patches currently in stable-queue which might be from boris.brezillon@xxxxxxxxxxxxx are
queue-5.4/drm-panfrost-don-t-try-to-map-pages-that-are-already-mapped.patch
queue-5.4/drm-panfrost-clear-mmu-irqs-before-handling-the-fault.patch
