--- /dev/null
+From dab60582685aabdae2d4ff7ce716456bd0dc7a0f Mon Sep 17 00:00:00 2001
+From: Roman Li <Roman.Li@amd.com>
+Date: Wed, 17 Nov 2021 10:05:36 -0500
+Subject: drm/amd/display: Fix OLED brightness control on eDP
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+From: Roman Li <Roman.Li@amd.com>
+
+commit dab60582685aabdae2d4ff7ce716456bd0dc7a0f upstream.
+
+[Why]
+After commit ("drm/amdgpu/display: add support for multiple backlights")
+number of eDPs is defined while registering backlight device.
+However the panel's extended caps get updated once before register call.
+That leads to regression with extended caps like oled brightness control.
+
+[How]
+Update connector ext caps after register_backlight_device
+
+Fixes: 7fd13baeb7a3a4 ("drm/amdgpu/display: add support for multiple backlights")
+Link: https://www.reddit.com/r/AMDLaptops/comments/qst0fm/after_updating_to_linux_515_my_brightness/
+
+Signed-off-by: Roman Li <Roman.Li@amd.com>
+Tested-by: Samuel Čavoj <samuel@cavoj.net>
+Acked-by: Alex Deucher <alexander.deucher@amd.com>
+Reviewed-by: Jasdeep Dhillon <Jasdeep.Dhillon@amd.com>
+Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
+Cc: stable@vger.kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
++++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+@@ -3846,6 +3846,9 @@ static int amdgpu_dm_initialize_drm_devi
+ } else if (dc_link_detect(link, DETECT_REASON_BOOT)) {
+ amdgpu_dm_update_connector_after_detect(aconnector);
+ register_backlight_device(dm, link);
++
++ if (dm->num_of_edps)
++ update_connector_ext_caps(aconnector);
+ if (amdgpu_dc_feature_mask & DC_PSR_MASK)
+ amdgpu_dm_set_psr_caps(link);
+ }
--- /dev/null
+From c1e63117711977cc4295b2ce73de29dd17066c82 Mon Sep 17 00:00:00 2001
+From: David Hildenbrand <david@redhat.com>
+Date: Fri, 19 Nov 2021 16:43:58 -0800
+Subject: proc/vmcore: fix clearing user buffer by properly using clear_user()
+
+From: David Hildenbrand <david@redhat.com>
+
+commit c1e63117711977cc4295b2ce73de29dd17066c82 upstream.
+
+To clear a user buffer we cannot simply use memset, we have to use
+clear_user(). With a virtio-mem device that registers a vmcore_cb and
+has some logically unplugged memory inside an added Linux memory block,
+I can easily trigger a BUG by copying the vmcore via "cp":
+
+ systemd[1]: Starting Kdump Vmcore Save Service...
+ kdump[420]: Kdump is using the default log level(3).
+ kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/
+ kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/
+ kdump[465]: saving vmcore-dmesg.txt complete
+ kdump[467]: saving vmcore
+ BUG: unable to handle page fault for address: 00007f2374e01000
+ #PF: supervisor write access in kernel mode
+ #PF: error_code(0x0003) - permissions violation
+ PGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867
+ Oops: 0003 [#1] PREEMPT SMP NOPTI
+ CPU: 0 PID: 468 Comm: cp Not tainted 5.15.0+ #6
+ Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 04/01/2014
+ RIP: 0010:read_from_oldmem.part.0.cold+0x1d/0x86
+ Code: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 <49> c7 45 00 00 00 00 00 49 c7 44 05 f8 00 00 00 00 48 83 e7 f81
+ RSP: 0018:ffffc9000073be08 EFLAGS: 00010212
+ RAX: 0000000000001000 RBX: 00000000002fd000 RCX: 00007f2374e01000
+ RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00007f2374e01008
+ RBP: 0000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50
+ R10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000
+ R13: 00007f2374e01000 R14: 0000000000000000 R15: ffff88807bd421e8
+ FS: 00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000
+ CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
+ CR2: 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0
+ Call Trace:
+ read_vmcore+0x236/0x2c0
+ proc_reg_read+0x55/0xa0
+ vfs_read+0x95/0x190
+ ksys_read+0x4f/0xc0
+ do_syscall_64+0x3b/0x90
+ entry_SYSCALL_64_after_hwframe+0x44/0xae
+
+Some x86-64 CPUs have a CPU feature called "Supervisor Mode Access
+Prevention (SMAP)", which is used to detect wrong access from the kernel
+to user buffers like this: SMAP triggers a permissions violation on
+wrong access. In the x86-64 variant of clear_user(), SMAP is properly
+handled via clac()+stac().
+
+To fix, properly use clear_user() when we're dealing with a user buffer.
+
+Link: https://lkml.kernel.org/r/20211112092750.6921-1-david@redhat.com
+Fixes: 997c136f518c ("fs/proc/vmcore.c: add hook to read_from_oldmem() to check for non-ram pages")
+Signed-off-by: David Hildenbrand <david@redhat.com>
+Acked-by: Baoquan He <bhe@redhat.com>
+Cc: Dave Young <dyoung@redhat.com>
+Cc: Baoquan He <bhe@redhat.com>
+Cc: Vivek Goyal <vgoyal@redhat.com>
+Cc: Philipp Rudo <prudo@redhat.com>
+Cc: <stable@vger.kernel.org>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/proc/vmcore.c | 16 ++++++++++------
+ 1 file changed, 10 insertions(+), 6 deletions(-)
+
+--- a/fs/proc/vmcore.c
++++ b/fs/proc/vmcore.c
+@@ -124,9 +124,13 @@ ssize_t read_from_oldmem(char *buf, size
+ nr_bytes = count;
+
+ /* If pfn is not ram, return zeros for sparse dump files */
+- if (pfn_is_ram(pfn) == 0)
+- memset(buf, 0, nr_bytes);
+- else {
++ if (pfn_is_ram(pfn) == 0) {
++ tmp = 0;
++ if (!userbuf)
++ memset(buf, 0, nr_bytes);
++ else if (clear_user(buf, nr_bytes))
++ tmp = -EFAULT;
++ } else {
+ if (encrypted)
+ tmp = copy_oldmem_page_encrypted(pfn, buf,
+ nr_bytes,
+@@ -135,10 +139,10 @@ ssize_t read_from_oldmem(char *buf, size
+ else
+ tmp = copy_oldmem_page(pfn, buf, nr_bytes,
+ offset, userbuf);
+-
+- if (tmp < 0)
+- return tmp;
+ }
++ if (tmp < 0)
++ return tmp;
++
+ *ppos += nr_bytes;
+ count -= nr_bytes;
+ buf += nr_bytes;
projects / thirdparty / kernel / stable-queue.git / commitdiff
