| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
Mark up the potential racy read in drm_mm_initialized(), as we want a
cheap and cheerful check:
[ 121.098731] BUG: KCSAN: data-race in _i915_gem_object_create_stolen [i915] / rm_hole
[ 121.098766]
[ 121.098789] write (marked) to 0xffff8881f01ed330 of 8 bytes by task 3568 on cpu 3:
[ 121.098831] rm_hole+0x64/0x140
[ 121.098860] drm_mm_insert_node_in_range+0x3d3/0x6c0
[ 121.099254] i915_gem_stolen_insert_node_in_range+0x91/0xe0 [i915]
[ 121.099646] _i915_gem_object_create_stolen+0x9d/0x100 [i915]
[ 121.100047] i915_gem_object_create_region+0x7a/0xa0 [i915]
[ 121.100451] i915_gem_object_create_stolen+0x33/0x50 [i915]
[ 121.100849] intel_engine_create_ring+0x1af/0x280 [i915]
[ 121.101242] __execlists_context_alloc+0xce/0x3d0 [i915]
[ 121.101635] execlists_context_alloc+0x25/0x40 [i915]
[ 121.102030] intel_context_alloc_state+0xb6/0xf0 [i915]
[ 121.102420] __intel_context_do_pin+0x1ff/0x220 [i915]
[ 121.102815] i915_gem_do_execbuffer+0x46b4/0x4c20 [i915]
[ 121.103211] i915_gem_execbuffer2_ioctl+0x2c3/0x580 [i915]
[ 121.103244] drm_ioctl_kernel+0xe4/0x120
[ 121.103269] drm_ioctl+0x297/0x4c7
[ 121.103296] ksys_ioctl+0x89/0xb0
[ 121.103321] __x64_sys_ioctl+0x42/0x60
[ 121.103349] do_syscall_64+0x6e/0x2c0
[ 121.103377] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 121.103403]
[ 121.103426] read to 0xffff8881f01ed330 of 8 bytes by task 3109 on cpu 1:
[ 121.103819] _i915_gem_object_create_stolen+0x30/0x100 [i915]
[ 121.104228] i915_gem_object_create_region+0x7a/0xa0 [i915]
[ 121.104631] i915_gem_object_create_stolen+0x33/0x50 [i915]
[ 121.105025] intel_engine_create_ring+0x1af/0x280 [i915]
[ 121.105420] __execlists_context_alloc+0xce/0x3d0 [i915]
[ 121.105818] execlists_context_alloc+0x25/0x40 [i915]
[ 121.106202] intel_context_alloc_state+0xb6/0xf0 [i915]
[ 121.106595] __intel_context_do_pin+0x1ff/0x220 [i915]
[ 121.106985] i915_gem_do_execbuffer+0x46b4/0x4c20 [i915]
[ 121.107375] i915_gem_execbuffer2_ioctl+0x2c3/0x580 [i915]
[ 121.107409] drm_ioctl_kernel+0xe4/0x120
[ 121.107437] drm_ioctl+0x297/0x4c7
[ 121.107464] ksys_ioctl+0x89/0xb0
[ 121.107489] __x64_sys_ioctl+0x42/0x60
[ 121.107511] do_syscall_64+0x6e/0x2c0
[ 121.107535] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200309121529.16497-1-chris@chris-wilson.co.uk
|
|
Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.
To avoid these problems, lift such variables up into the next code
block.
drivers/gpu/drm/drm_edid.c: In function ‘drm_edid_to_eld’:
drivers/gpu/drm/drm_edid.c:4395:9: warning: statement will never be
executed [-Wswitch-unreachable]
4395 | int sad_count;
| ^~~~~~~~~
[1] https://bugs.llvm.org/show_bug.cgi?id=44916
v2: move into function block instead being switch-local (Ville Syrjälä)
Signed-off-by: Kees Cook <keescook@chromium.org>
[danvet: keep the changelog]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/202003060930.DDCCB6659@keescook
|
|
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
|
|
Fix kernel doc comments to avoid warnings when compiling with W=1.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200306102937.4932-2-benjamin.gaignard@st.com
|
|
Fix kernel doc comments to avoid warnings when compiling with W=1.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200306102937.4932-3-benjamin.gaignard@st.com
|
|
Fix kernel doc comments to avoid warnings when compiling with W=1.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200306102937.4932-1-benjamin.gaignard@st.com
|
|
Fix kernel doc comments to avoid warnings when compiling with W=1.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200306102937.4932-4-benjamin.gaignard@st.com
|
Chris Wilson
Kees Cook
Gustavo A. R. Silva
Benjamin Gaignard