<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/include/drm, branch v5.15.88</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.88</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.88'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2022-09-05T08:30:03+00:00</updated>
<entry>
<title>drm/bridge: Add stubs for devm_drm_of_get_bridge when OF is disabled</title>
<updated>2022-09-05T08:30:03+00:00</updated>
<author>
<name>Maxime Ripard</name>
<email>maxime@cerno.tech</email>
</author>
<published>2021-09-28T18:13:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f8b07c05b69969c41efafda7022d6cb184d61bf9'/>
<id>urn:sha1:f8b07c05b69969c41efafda7022d6cb184d61bf9</id>
<content type='text'>
commit 59050d783848d9b62e9d8fb6ce0cd00771c2bf87 upstream.

If CONFIG_OF is disabled, devm_drm_of_get_bridge won't be compiled in
and drivers using that function will fail to build.

Add an inline stub so that we can still build-test those cases.

Reported-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Maxime Ripard &lt;maxime@cerno.tech&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt; # build-tested
Link: https://patchwork.freedesktop.org/patch/msgid/20210928181333.1176840-1-maxime@cerno.tech
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm/bridge: Add a function to abstract away panels</title>
<updated>2022-08-17T12:23:24+00:00</updated>
<author>
<name>Maxime Ripard</name>
<email>maxime@cerno.tech</email>
</author>
<published>2021-09-10T13:09:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ed486d15084f7429298ca4c577e5647a3fdca934'/>
<id>urn:sha1:ed486d15084f7429298ca4c577e5647a3fdca934</id>
<content type='text'>
[ Upstream commit 87ea95808d53e56b03e620e8f8f3add48899a88d ]

Display drivers so far need to have a lot of boilerplate to first
retrieve either the panel or bridge that they are connected to using
drm_of_find_panel_or_bridge(), and then either deal with each with ad-hoc
functions or create a drm panel bridge through drm_panel_bridge_add.

In order to reduce the boilerplate and hopefully create a path of least
resistance towards using the DRM panel bridge layer, let's create the
function devm_drm_of_get_bridge() to reduce that boilerplate.

Signed-off-by: Maxime Ripard &lt;maxime@cerno.tech&gt;
Reviewed-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20210910130941.1740182-2-maxime@cerno.tech
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/shmem-helper: Pass GEM shmem object in public interfaces</title>
<updated>2022-08-17T12:23:19+00:00</updated>
<author>
<name>Thomas Zimmermann</name>
<email>tzimmermann@suse.de</email>
</author>
<published>2021-11-08T09:31:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ff0087df198d9be0e78281d044946185f0fc437e'/>
<id>urn:sha1:ff0087df198d9be0e78281d044946185f0fc437e</id>
<content type='text'>
[ Upstream commit a193f3b4e050e35c506a34d0870c838d8e0b0449 ]

Change all GEM SHMEM object functions that receive a GEM object
of type struct drm_gem_object to expect an object of type
struct drm_gem_shmem_object instead.

This change reduces the number of upcasts from struct drm_gem_object
by moving them into callers. The C compiler can now verify that the
GEM SHMEM functions are called with the correct type.

For consistency, the patch also renames drm_gem_shmem_free_object to
drm_gem_shmem_free. It further updates documentation for a number of
functions.

v3:
	* fix docs for drm_gem_shmem_object_free()
v2:
	* mention _object_ callbacks in docs (Daniel)

Signed-off-by: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Acked-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20211108093149.7226-4-tzimmermann@suse.de
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/shmem-helper: Export dedicated wrappers for GEM object functions</title>
<updated>2022-08-17T12:23:18+00:00</updated>
<author>
<name>Thomas Zimmermann</name>
<email>tzimmermann@suse.de</email>
</author>
<published>2021-11-08T09:31:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=4109ff9e7b95775ca84cbde9745569cfc85b672e'/>
<id>urn:sha1:4109ff9e7b95775ca84cbde9745569cfc85b672e</id>
<content type='text'>
[ Upstream commit c7fbcb7149ff9321bbbcc93c9920de534ea8102c ]

Wrap GEM SHMEM functions for struct drm_gem_object_funcs and update
all callers. This will allow for an update of the public interfaces
of the GEM SHMEM helper library.

v2:
	* fix docs for drm_gem_shmem_object_print_info()

Signed-off-by: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Acked-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20211108093149.7226-3-tzimmermann@suse.de
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/shmem-helper: Unexport drm_gem_shmem_create_with_handle()</title>
<updated>2022-08-17T12:23:18+00:00</updated>
<author>
<name>Thomas Zimmermann</name>
<email>tzimmermann@suse.de</email>
</author>
<published>2021-11-08T09:31:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=a3f82087b768fd9d67595857e0949419ca49fe28'/>
<id>urn:sha1:a3f82087b768fd9d67595857e0949419ca49fe28</id>
<content type='text'>
[ Upstream commit 5a363c20673308e968b6640deb73d7bf77e8b463 ]

Turn drm_gem_shmem_create_with_handle() into an internal helper
function. It's not used outside of the compilation unit.

Signed-off-by: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Acked-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20211108093149.7226-2-tzimmermann@suse.de
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm: fix EDID struct for old ARM OABI format</title>
<updated>2022-06-09T08:22:44+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-05-28T18:08:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=710051ebb77b785d637417564be7fed4c13c6ce0'/>
<id>urn:sha1:710051ebb77b785d637417564be7fed4c13c6ce0</id>
<content type='text'>
[ Upstream commit 47f15561b69e226bfc034e94ff6dbec51a4662af ]

When building the kernel for arm with the "-mabi=apcs-gnu" option, gcc
will force alignment of all structures and unions to a word boundary
(see also STRUCTURE_SIZE_BOUNDARY and the "-mstructure-size-boundary=XX"
option if you're a gcc person), even when the members of said structures
do not want or need said alignment.

This completely messes up the structure alignment of 'struct edid' on
those targets, because even though all the embedded structures are
marked with "__attribute__((packed))", the unions that contain them are
not.

This was exposed by commit f1e4c916f97f ("drm/edid: add EDID block count
and size helpers"), but the bug is pre-existing.  That commit just made
the structure layout problem cause a build failure due to the addition
of the

        BUILD_BUG_ON(sizeof(*edid) != EDID_LENGTH);

sanity check in drivers/gpu/drm/drm_edid.c:edid_block_data().

This legacy union alignment should probably not be used in the first
place, but we can fix the layout by adding the packed attribute to the
union entries even when each member is already packed and it shouldn't
matter in a sane build environment.

You can see this issue with a trivial test program:

  union {
	struct {
		char c[5];
	};
	struct {
		char d;
		unsigned e;
	} __attribute__((packed));
  } a = { "1234" };

where building this with a normal "gcc -S" will result in the expected
5-byte size of said union:

	.type	a, @object
	.size	a, 5

but with an ARM compiler and the old ABI:

    arm-linux-gnu-gcc -mabi=apcs-gnu -mfloat-abi=soft -S t.c

you get

	.type	a, %object
	.size	a, 8

instead, because even though each member of the union is packed, the
union itself still gets aligned.

This was reported by Sudip for the spear3xx_defconfig target.

Link: https://lore.kernel.org/lkml/YpCUzStDnSgQLNFN@debian/
Reported-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Maxime Ripard &lt;mripard@kernel.org&gt;
Cc: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Cc: David Airlie &lt;airlied@linux.ie&gt;
Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/connector: Fix typo in documentation</title>
<updated>2022-04-08T12:24:12+00:00</updated>
<author>
<name>Maxime Ripard</name>
<email>maxime@cerno.tech</email>
</author>
<published>2022-02-02T09:43:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=b9cf1208af36f6552e6f3b8fdf364983e3cc8e60'/>
<id>urn:sha1:b9cf1208af36f6552e6f3b8fdf364983e3cc8e60</id>
<content type='text'>
commit dca384a3bf5af1c781cfa6aec63904bdb5018c36 upstream.

Commit 4adc33f36d80 ("drm/edid: Split deep color modes between RGB and
YUV444") introduced two new variables in struct drm_display_info and
their documentation, but the documentation part had a typo resulting in
a doc build warning.

Fixes: 4adc33f36d80 ("drm/edid: Split deep color modes between RGB and YUV444")
Reported-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Maxime Ripard &lt;maxime@cerno.tech&gt;
Reviewed-by: Simon Ser &lt;contact@emersion.fr&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20220202094340.875190-1-maxime@cerno.tech
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm/dp: Fix off-by-one in register cache size</title>
<updated>2022-04-08T12:24:04+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2022-02-25T03:56:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=e912d697400c5f4bc8c1c8090416dad6c59cb28c'/>
<id>urn:sha1:e912d697400c5f4bc8c1c8090416dad6c59cb28c</id>
<content type='text'>
commit d4da1f27396fb1dde079447a3612f4f512caed07 upstream.

The pcon_dsc_dpcd array holds 13 registers (0x92 through 0x9E). Fix the
math to calculate the max size. Found from a -Warray-bounds build:

drivers/gpu/drm/drm_dp_helper.c: In function 'drm_dp_pcon_dsc_bpp_incr':
drivers/gpu/drm/drm_dp_helper.c:3130:28: error: array subscript 12 is outside array bounds of 'const u8[12]' {aka 'const unsigned char[12]'} [-Werror=array-bounds]
 3130 |         buf = pcon_dsc_dpcd[DP_PCON_DSC_BPP_INCR - DP_PCON_DSC_ENCODER];
      |               ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/drm_dp_helper.c:3126:39: note: while referencing 'pcon_dsc_dpcd'
 3126 | int drm_dp_pcon_dsc_bpp_incr(const u8 pcon_dsc_dpcd[DP_PCON_DSC_ENCODER_CAP_SIZE])
      |                              ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Cc: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Maxime Ripard &lt;mripard@kernel.org&gt;
Cc: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Cc: David Airlie &lt;airlied@linux.ie&gt;
Cc: dri-devel@lists.freedesktop.org
Fixes: e2e16da398d9 ("drm/dp_helper: Add support for Configuring DSC for HDMI2.1 Pcon")
Cc: stable@vger.kernel.org
Reviewed-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Link: https://lore.kernel.org/lkml/20211214001849.GA62559@embeddedor/
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Link: https://lore.kernel.org/r/20220105173310.2420598-1-keescook@chromium.org
Signed-off-by: Thierry Reding &lt;treding@nvidia.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20220225035610.2552144-2-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm/edid: Split deep color modes between RGB and YUV444</title>
<updated>2022-04-08T12:23:25+00:00</updated>
<author>
<name>Maxime Ripard</name>
<email>maxime@cerno.tech</email>
</author>
<published>2022-01-20T15:16:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=da491fc54e4e387419948840636df15f4a611ec4'/>
<id>urn:sha1:da491fc54e4e387419948840636df15f4a611ec4</id>
<content type='text'>
[ Upstream commit 4adc33f36d80489339f1b43dfeee96bb9ea8e459 ]

The current code assumes that the RGB444 and YUV444 formats are the
same, but the HDMI 2.0 specification states that:

   The three DC_XXbit bits above only indicate support for RGB 4:4:4 at
   that pixel size. Support for YCBCR 4:4:4 in Deep Color modes is
   indicated with the DC_Y444 bit. If DC_Y444 is set, then YCBCR 4:4:4
   is supported for all modes indicated by the DC_XXbit flags.

So if we have YUV444 support and any DC_XXbit flag set but the DC_Y444
flag isn't, we'll assume that we support that deep colour mode for
YUV444 which breaks the specification.

In order to fix this, let's split the edid_hdmi_dc_modes field in struct
drm_display_info into two fields, one for RGB444 and one for YUV444.

Suggested-by: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;
Fixes: d0c94692e0a3 ("drm/edid: Parse and handle HDMI deep color modes.")
Signed-off-by: Maxime Ripard &lt;maxime@cerno.tech&gt;
Reviewed-by: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20220120151625.594595-4-maxime@cerno.tech
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/ttm: remove ttm_bo_vm_insert_huge()</title>
<updated>2021-11-18T18:17:08+00:00</updated>
<author>
<name>Jason Gunthorpe</name>
<email>jgg@nvidia.com</email>
</author>
<published>2021-10-19T23:27:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=71fb40ae9b07578b3aeebf78fcbb3394810acd9a'/>
<id>urn:sha1:71fb40ae9b07578b3aeebf78fcbb3394810acd9a</id>
<content type='text'>
[ Upstream commit 0d979509539ed1df883a30d442177ca7be609565 ]

The huge page functionality in TTM does not work safely because PUD and
PMD entries do not have a special bit.

get_user_pages_fast() considers any page that passed pmd_huge() as
usable:

	if (unlikely(pmd_trans_huge(pmd) || pmd_huge(pmd) ||
		     pmd_devmap(pmd))) {

And vmf_insert_pfn_pmd_prot() unconditionally sets

	entry = pmd_mkhuge(pfn_t_pmd(pfn, prot));

eg on x86 the page will be _PAGE_PRESENT | PAGE_PSE.

As such gup_huge_pmd() will try to deref a struct page:

	head = try_grab_compound_head(pmd_page(orig), refs, flags);

and thus crash.

Thomas further notices that the drivers are not expecting the struct page
to be used by anything - in particular the refcount incr above will cause
them to malfunction.

Thus everything about this is not able to fully work correctly considering
GUP_fast. Delete it entirely. It can return someday along with a proper
PMD/PUD_SPECIAL bit in the page table itself to gate GUP_fast.

Fixes: 314b6580adc5 ("drm/ttm, drm/vmwgfx: Support huge TTM pagefaults")
Signed-off-by: Jason Gunthorpe &lt;jgg@nvidia.com&gt;
Reviewed-by: Thomas Hellström &lt;thomas.helllstrom@linux.intel.com&gt;
Reviewed-by: Christian König &lt;christian.koenig@amd.com&gt;
[danvet: Update subject per Thomas' &amp;Christian's review]
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/0-v2-a44694790652+4ac-ttm_pmd_jgg@nvidia.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
