diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.14/950-0175-drm-vc4-Fix-false-positive-WARN-backtrace-on-refcoun.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.14/950-0175-drm-vc4-Fix-false-positive-WARN-backtrace-on-refcoun.patch | 41 |
1 files changed, 0 insertions, 41 deletions
diff --git a/target/linux/brcm2708/patches-4.14/950-0175-drm-vc4-Fix-false-positive-WARN-backtrace-on-refcoun.patch b/target/linux/brcm2708/patches-4.14/950-0175-drm-vc4-Fix-false-positive-WARN-backtrace-on-refcoun.patch deleted file mode 100644 index 0d3b4520d3..0000000000 --- a/target/linux/brcm2708/patches-4.14/950-0175-drm-vc4-Fix-false-positive-WARN-backtrace-on-refcoun.patch +++ /dev/null @@ -1,41 +0,0 @@ -From 5537bac0e5c8f3634c5595c21c7d63f0c0263e0e Mon Sep 17 00:00:00 2001 -From: Boris Brezillon <boris.brezillon@free-electrons.com> -Date: Wed, 22 Nov 2017 21:39:28 +0100 -Subject: [PATCH 175/454] drm/vc4: Fix false positive WARN() backtrace on - refcount_inc() usage - -With CONFIG_REFCOUNT_FULL enabled, refcount_inc() complains when it's -passed a refcount object that has its counter set to 0. In this driver, -this is a valid use case since we want to increment ->usecnt only when -the BO object starts to be used by real HW components and this is -definitely not the case when the BO is created. - -Fix the problem by using refcount_inc_not_zero() instead of -refcount_inc() and fallback to refcount_set(1) when -refcount_inc_not_zero() returns false. Note that this 2-steps operation -is not racy here because the whole section is protected by a mutex -which guarantees that the counter does not change between the -refcount_inc_not_zero() and refcount_set() calls. - -Fixes: b9f19259b84d ("drm/vc4: Add the DRM_IOCTL_VC4_GEM_MADVISE ioctl") -Reported-by: Stefan Wahren <stefan.wahren@i2se.com> -Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> -Acked-by: Eric Anholt <eric@anholt.net> -Link: https://patchwork.freedesktop.org/patch/msgid/20171122203928.28135-1-boris.brezillon@free-electrons.com -(cherry picked from commit 5bfd40139d55790cbc8e56ad1ce4f974f1fa186d) ---- - drivers/gpu/drm/vc4/vc4_bo.c | 3 ++- - 1 file changed, 2 insertions(+), 1 deletion(-) - ---- a/drivers/gpu/drm/vc4/vc4_bo.c -+++ b/drivers/gpu/drm/vc4/vc4_bo.c -@@ -639,7 +639,8 @@ int vc4_bo_inc_usecnt(struct vc4_bo *bo) - mutex_lock(&bo->madv_lock); - switch (bo->madv) { - case VC4_MADV_WILLNEED: -- refcount_inc(&bo->usecnt); -+ if (!refcount_inc_not_zero(&bo->usecnt)) -+ refcount_set(&bo->usecnt, 1); - ret = 0; - break; - case VC4_MADV_DONTNEED: |