<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/video, branch v4.4.201</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>video: ssd1307fb: Start page range at page_offset</title>
<updated>2019-10-07T19:00:59+00:00</updated>
<author>
<name>Marko Kohtala</name>
<email>marko.kohtala@okoko.fi</email>
</author>
<published>2019-06-18T07:41:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=512013196156b47397eac3b4c1a046898629be40'/>
<id>512013196156b47397eac3b4c1a046898629be40</id>
<content type='text'>
[ Upstream commit dd9782834dd9dde3624ff1acea8859f3d3e792d4 ]

The page_offset was only applied to the end of the page range. This caused
the display updates to cause a scrolling effect on the display because the
amount of data written to the display did not match the range display
expected.

Fixes: 301bc0675b67 ("video: ssd1307fb: Make use of horizontal addressing mode")
Signed-off-by: Marko Kohtala &lt;marko.kohtala@okoko.fi&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Rob Herring &lt;robh+dt@kernel.org&gt;
Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Cc: David Airlie &lt;airlied@linux.ie&gt;
Cc: Michal Vokáč &lt;michal.vokac@ysoft.com&gt;
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20190618074111.9309-4-marko.kohtala@okoko.fi
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit dd9782834dd9dde3624ff1acea8859f3d3e792d4 ]

The page_offset was only applied to the end of the page range. This caused
the display updates to cause a scrolling effect on the display because the
amount of data written to the display did not match the range display
expected.

Fixes: 301bc0675b67 ("video: ssd1307fb: Make use of horizontal addressing mode")
Signed-off-by: Marko Kohtala &lt;marko.kohtala@okoko.fi&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Rob Herring &lt;robh+dt@kernel.org&gt;
Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Cc: David Airlie &lt;airlied@linux.ie&gt;
Cc: Michal Vokáč &lt;michal.vokac@ysoft.com&gt;
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20190618074111.9309-4-marko.kohtala@okoko.fi
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>video: imsttfb: fix potential NULL pointer dereferences</title>
<updated>2019-06-22T06:18:21+00:00</updated>
<author>
<name>Kangjie Lu</name>
<email>kjlu@umn.edu</email>
</author>
<published>2019-04-01T15:46:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c869210e0ac6af93df8c2f68c80c1978be00d4f7'/>
<id>c869210e0ac6af93df8c2f68c80c1978be00d4f7</id>
<content type='text'>
[ Upstream commit 1d84353d205a953e2381044953b7fa31c8c9702d ]

In case ioremap fails, the fix releases resources and returns
-ENOMEM to avoid NULL pointer dereferences.

Signed-off-by: Kangjie Lu &lt;kjlu@umn.edu&gt;
Cc: Aditya Pakki &lt;pakki001@umn.edu&gt;
Cc: Finn Thain &lt;fthain@telegraphics.com.au&gt;
Cc: Rob Herring &lt;robh@kernel.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
[b.zolnierkie: minor patch summary fixup]
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1d84353d205a953e2381044953b7fa31c8c9702d ]

In case ioremap fails, the fix releases resources and returns
-ENOMEM to avoid NULL pointer dereferences.

Signed-off-by: Kangjie Lu &lt;kjlu@umn.edu&gt;
Cc: Aditya Pakki &lt;pakki001@umn.edu&gt;
Cc: Finn Thain &lt;fthain@telegraphics.com.au&gt;
Cc: Rob Herring &lt;robh@kernel.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
[b.zolnierkie: minor patch summary fixup]
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>video: hgafb: fix potential NULL pointer dereference</title>
<updated>2019-06-22T06:18:21+00:00</updated>
<author>
<name>Kangjie Lu</name>
<email>kjlu@umn.edu</email>
</author>
<published>2019-04-01T15:46:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5c7fbc5f6a7d526054e0b11df8053e0841fb8a29'/>
<id>5c7fbc5f6a7d526054e0b11df8053e0841fb8a29</id>
<content type='text'>
[ Upstream commit ec7f6aad57ad29e4e66cc2e18e1e1599ddb02542 ]

When ioremap fails, hga_vram should not be dereferenced. The fix
check the failure to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu &lt;kjlu@umn.edu&gt;
Cc: Aditya Pakki &lt;pakki001@umn.edu&gt;
Cc: Ferenc Bakonyi &lt;fero@drama.obuda.kando.hu&gt;
[b.zolnierkie: minor patch summary fixup]
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ec7f6aad57ad29e4e66cc2e18e1e1599ddb02542 ]

When ioremap fails, hga_vram should not be dereferenced. The fix
check the failure to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu &lt;kjlu@umn.edu&gt;
Cc: Aditya Pakki &lt;pakki001@umn.edu&gt;
Cc: Ferenc Bakonyi &lt;fero@drama.obuda.kando.hu&gt;
[b.zolnierkie: minor patch summary fixup]
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fbdev: fix WARNING in __alloc_pages_nodemask bug</title>
<updated>2019-06-11T10:23:52+00:00</updated>
<author>
<name>Jiufei Xue</name>
<email>jiufei.xue@linux.alibaba.com</email>
</author>
<published>2019-04-11T17:25:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=28eeeb86046e4a0e99881b15372ac8c0a0294698'/>
<id>28eeeb86046e4a0e99881b15372ac8c0a0294698</id>
<content type='text'>
commit 8c40292be9169a9cbe19aadd1a6fc60cbd1af82f upstream.

Syzkaller hit 'WARNING in __alloc_pages_nodemask' bug.

WARNING: CPU: 1 PID: 1473 at mm/page_alloc.c:4377
__alloc_pages_nodemask+0x4da/0x2130
Kernel panic - not syncing: panic_on_warn set ...

Call Trace:
 alloc_pages_current+0xb1/0x1e0
 kmalloc_order+0x1f/0x60
 kmalloc_order_trace+0x1d/0x120
 fb_alloc_cmap_gfp+0x85/0x2b0
 fb_set_user_cmap+0xff/0x370
 do_fb_ioctl+0x949/0xa20
 fb_ioctl+0xdd/0x120
 do_vfs_ioctl+0x186/0x1070
 ksys_ioctl+0x89/0xa0
 __x64_sys_ioctl+0x74/0xb0
 do_syscall_64+0xc8/0x550
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

This is a warning about order &gt;= MAX_ORDER and the order is from
userspace ioctl. Add flag __NOWARN to silence this warning.

Signed-off-by: Jiufei Xue &lt;jiufei.xue@linux.alibaba.com&gt;
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8c40292be9169a9cbe19aadd1a6fc60cbd1af82f upstream.

Syzkaller hit 'WARNING in __alloc_pages_nodemask' bug.

WARNING: CPU: 1 PID: 1473 at mm/page_alloc.c:4377
__alloc_pages_nodemask+0x4da/0x2130
Kernel panic - not syncing: panic_on_warn set ...

Call Trace:
 alloc_pages_current+0xb1/0x1e0
 kmalloc_order+0x1f/0x60
 kmalloc_order_trace+0x1d/0x120
 fb_alloc_cmap_gfp+0x85/0x2b0
 fb_set_user_cmap+0xff/0x370
 do_fb_ioctl+0x949/0xa20
 fb_ioctl+0xdd/0x120
 do_vfs_ioctl+0x186/0x1070
 ksys_ioctl+0x89/0xa0
 __x64_sys_ioctl+0x74/0xb0
 do_syscall_64+0xc8/0x550
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

This is a warning about order &gt;= MAX_ORDER and the order is from
userspace ioctl. Add flag __NOWARN to silence this warning.

Signed-off-by: Jiufei Xue &lt;jiufei.xue@linux.alibaba.com&gt;
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>fbdev: fix divide error in fb_var_to_videomode</title>
<updated>2019-06-11T10:23:52+00:00</updated>
<author>
<name>Shile Zhang</name>
<email>shile.zhang@linux.alibaba.com</email>
</author>
<published>2019-04-01T15:47:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6bc15390790053b64c46dea03c39a1f7728110b7'/>
<id>6bc15390790053b64c46dea03c39a1f7728110b7</id>
<content type='text'>
commit cf84807f6dd0be5214378e66460cfc9187f532f9 upstream.

To fix following divide-by-zero error found by Syzkaller:

  divide error: 0000 [#1] SMP PTI
  CPU: 7 PID: 8447 Comm: test Kdump: loaded Not tainted 4.19.24-8.al7.x86_64 #1
  Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  RIP: 0010:fb_var_to_videomode+0xae/0xc0
  Code: 04 44 03 46 78 03 4e 7c 44 03 46 68 03 4e 70 89 ce d1 ee 69 c0 e8 03 00 00 f6 c2 01 0f 45 ce 83 e2 02 8d 34 09 0f 45 ce 31 d2 &lt;41&gt; f7 f0 31 d2 f7 f1 89 47 08 f3 c3 66 0f 1f 44 00 00 0f 1f 44 00
  RSP: 0018:ffffb7e189347bf0 EFLAGS: 00010246
  RAX: 00000000e1692410 RBX: ffffb7e189347d60 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb7e189347c10
  RBP: ffff99972a091c00 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000100
  R13: 0000000000010000 R14: 00007ffd66baf6d0 R15: 0000000000000000
  FS:  00007f2054d11740(0000) GS:ffff99972fbc0000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f205481fd20 CR3: 00000004288a0001 CR4: 00000000001606a0
  Call Trace:
   fb_set_var+0x257/0x390
   ? lookup_fast+0xbb/0x2b0
   ? fb_open+0xc0/0x140
   ? chrdev_open+0xa6/0x1a0
   do_fb_ioctl+0x445/0x5a0
   do_vfs_ioctl+0x92/0x5f0
   ? __alloc_fd+0x3d/0x160
   ksys_ioctl+0x60/0x90
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x5b/0x190
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7f20548258d7
  Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48

It can be triggered easily with following test code:

  #include &lt;linux/fb.h&gt;
  #include &lt;fcntl.h&gt;
  #include &lt;sys/ioctl.h&gt;
  int main(void)
  {
          struct fb_var_screeninfo var = {.activate = 0x100, .pixclock = 60};
          int fd = open("/dev/fb0", O_RDWR);
          if (fd &lt; 0)
                  return 1;

          if (ioctl(fd, FBIOPUT_VSCREENINFO, &amp;var))
                  return 1;

          return 0;
  }

Signed-off-by: Shile Zhang &lt;shile.zhang@linux.alibaba.com&gt;
Cc: Fredrik Noring &lt;noring@nocrew.org&gt;
Cc: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Reviewed-by: Mukesh Ojha &lt;mojha@codeaurora.org&gt;
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit cf84807f6dd0be5214378e66460cfc9187f532f9 upstream.

To fix following divide-by-zero error found by Syzkaller:

  divide error: 0000 [#1] SMP PTI
  CPU: 7 PID: 8447 Comm: test Kdump: loaded Not tainted 4.19.24-8.al7.x86_64 #1
  Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  RIP: 0010:fb_var_to_videomode+0xae/0xc0
  Code: 04 44 03 46 78 03 4e 7c 44 03 46 68 03 4e 70 89 ce d1 ee 69 c0 e8 03 00 00 f6 c2 01 0f 45 ce 83 e2 02 8d 34 09 0f 45 ce 31 d2 &lt;41&gt; f7 f0 31 d2 f7 f1 89 47 08 f3 c3 66 0f 1f 44 00 00 0f 1f 44 00
  RSP: 0018:ffffb7e189347bf0 EFLAGS: 00010246
  RAX: 00000000e1692410 RBX: ffffb7e189347d60 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb7e189347c10
  RBP: ffff99972a091c00 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000100
  R13: 0000000000010000 R14: 00007ffd66baf6d0 R15: 0000000000000000
  FS:  00007f2054d11740(0000) GS:ffff99972fbc0000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f205481fd20 CR3: 00000004288a0001 CR4: 00000000001606a0
  Call Trace:
   fb_set_var+0x257/0x390
   ? lookup_fast+0xbb/0x2b0
   ? fb_open+0xc0/0x140
   ? chrdev_open+0xa6/0x1a0
   do_fb_ioctl+0x445/0x5a0
   do_vfs_ioctl+0x92/0x5f0
   ? __alloc_fd+0x3d/0x160
   ksys_ioctl+0x60/0x90
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x5b/0x190
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7f20548258d7
  Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 &lt;48&gt; 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48

It can be triggered easily with following test code:

  #include &lt;linux/fb.h&gt;
  #include &lt;fcntl.h&gt;
  #include &lt;sys/ioctl.h&gt;
  int main(void)
  {
          struct fb_var_screeninfo var = {.activate = 0x100, .pixclock = 60};
          int fd = open("/dev/fb0", O_RDWR);
          if (fd &lt; 0)
                  return 1;

          if (ioctl(fd, FBIOPUT_VSCREENINFO, &amp;var))
                  return 1;

          return 0;
  }

Signed-off-by: Shile Zhang &lt;shile.zhang@linux.alibaba.com&gt;
Cc: Fredrik Noring &lt;noring@nocrew.org&gt;
Cc: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Reviewed-by: Mukesh Ojha &lt;mojha@codeaurora.org&gt;
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>fbdev: sm712fb: fix memory frequency by avoiding a switch/case fallthrough</title>
<updated>2019-06-11T10:23:50+00:00</updated>
<author>
<name>Yifeng Li</name>
<email>tomli@tomli.me</email>
</author>
<published>2019-04-02T15:14:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=31943685dd499b0599113e6db5ee9c462e0e7e6a'/>
<id>31943685dd499b0599113e6db5ee9c462e0e7e6a</id>
<content type='text'>
commit 9dc20113988b9a75ea6b3abd68dc45e2d73ccdab upstream.

A fallthrough in switch/case was introduced in f627caf55b8e ("fbdev:
sm712fb: fix crashes and garbled display during DPMS modesetting"),
due to my copy-paste error, which would cause the memory clock frequency
for SM720 to be programmed to SM712.

Since it only reprograms the clock to a different frequency, it's only
a benign issue without visible side-effect, so it also evaded Sudip
Mukherjee's code review and regression tests. scripts/checkpatch.pl
also failed to discover the issue, possibly due to nested switch
statements.

This issue was found by Stephen Rothwell by building linux-next with
-Wimplicit-fallthrough.

Reported-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Fixes: f627caf55b8e ("fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting")
Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Cc: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: "Gustavo A. R. Silva" &lt;gustavo@embeddedor.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9dc20113988b9a75ea6b3abd68dc45e2d73ccdab upstream.

A fallthrough in switch/case was introduced in f627caf55b8e ("fbdev:
sm712fb: fix crashes and garbled display during DPMS modesetting"),
due to my copy-paste error, which would cause the memory clock frequency
for SM720 to be programmed to SM712.

Since it only reprograms the clock to a different frequency, it's only
a benign issue without visible side-effect, so it also evaded Sudip
Mukherjee's code review and regression tests. scripts/checkpatch.pl
also failed to discover the issue, possibly due to nested switch
statements.

This issue was found by Stephen Rothwell by building linux-next with
-Wimplicit-fallthrough.

Reported-by: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Fixes: f627caf55b8e ("fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting")
Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Cc: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: "Gustavo A. R. Silva" &lt;gustavo@embeddedor.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting</title>
<updated>2019-06-11T10:23:48+00:00</updated>
<author>
<name>Yifeng Li</name>
<email>tomli@tomli.me</email>
</author>
<published>2019-04-01T15:46:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0dc2ad06ddad075cf31634ef808e6a55f3c339ba'/>
<id>0dc2ad06ddad075cf31634ef808e6a55f3c339ba</id>
<content type='text'>
commit f627caf55b8e735dcec8fa6538e9668632b55276 upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), blanking the display
or starting the X server will crash and freeze the system, or garble the
display.

Experiments showed this problem can mostly be solved by adjusting the
order of register writes. Also, sm712fb failed to consider the difference
of clock frequency when unblanking the display, and programs the clock for
SM712 to SM720.

Fix them by adjusting the order of register writes, and adding an
additional check for SM720 for programming the clock frequency.

Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Tested-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: Teddy Wang &lt;teddy.wang@siliconmotion.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;  # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f627caf55b8e735dcec8fa6538e9668632b55276 upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), blanking the display
or starting the X server will crash and freeze the system, or garble the
display.

Experiments showed this problem can mostly be solved by adjusting the
order of register writes. Also, sm712fb failed to consider the difference
of clock frequency when unblanking the display, and programs the clock for
SM712 to SM720.

Fix them by adjusting the order of register writes, and adding an
additional check for SM720 for programming the clock frequency.

Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Tested-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: Teddy Wang &lt;teddy.wang@siliconmotion.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;  # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>fbdev: sm712fb: use 1024x768 by default on non-MIPS, fix garbled display</title>
<updated>2019-06-11T10:23:48+00:00</updated>
<author>
<name>Yifeng Li</name>
<email>tomli@tomli.me</email>
</author>
<published>2019-04-01T15:46:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4673eae95b535cb28700d491705f67cc60239f8e'/>
<id>4673eae95b535cb28700d491705f67cc60239f8e</id>
<content type='text'>
commit 4ed7d2ccb7684510ec5f7a8f7ef534bc6a3d55b2 upstream.

Loongson MIPS netbooks use 1024x600 LCD panels, which is the original
target platform of this driver, but nearly all old x86 laptops have
1024x768. Lighting 768 panels using 600's timings would partially
garble the display. Since it's not possible to distinguish them reliably,
we change the default to 768, but keep 600 as-is on MIPS.

Further, earlier laptops, such as IBM Thinkpad 240X, has a 800x600 LCD
panel, this driver would probably garbled those display. As we don't
have one for testing, the original behavior of the driver is kept as-is,
but the problem has been documented is the comments.

Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Tested-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: Teddy Wang &lt;teddy.wang@siliconmotion.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;  # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4ed7d2ccb7684510ec5f7a8f7ef534bc6a3d55b2 upstream.

Loongson MIPS netbooks use 1024x600 LCD panels, which is the original
target platform of this driver, but nearly all old x86 laptops have
1024x768. Lighting 768 panels using 600's timings would partially
garble the display. Since it's not possible to distinguish them reliably,
we change the default to 768, but keep 600 as-is on MIPS.

Further, earlier laptops, such as IBM Thinkpad 240X, has a 800x600 LCD
panel, this driver would probably garbled those display. As we don't
have one for testing, the original behavior of the driver is kept as-is,
but the problem has been documented is the comments.

Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Tested-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: Teddy Wang &lt;teddy.wang@siliconmotion.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;  # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>fbdev: sm712fb: fix support for 1024x768-16 mode</title>
<updated>2019-06-11T10:23:48+00:00</updated>
<author>
<name>Yifeng Li</name>
<email>tomli@tomli.me</email>
</author>
<published>2019-04-01T15:46:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c996722f7fffe1cfe0e41d3105434224978df245'/>
<id>c996722f7fffe1cfe0e41d3105434224978df245</id>
<content type='text'>
commit 6053d3a4793e5bde6299ac5388e76a3bf679ff65 upstream.

In order to support the 1024x600 panel on Yeeloong Loongson MIPS
laptop, the original 1024x768-16 table was modified to 1024x600-16,
without leaving the original. It causes problem on x86 laptop as
the 1024x768-16 support was still claimed but not working.

Fix it by introducing the 1024x768-16 mode.

Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Tested-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: Teddy Wang &lt;teddy.wang@siliconmotion.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;  # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6053d3a4793e5bde6299ac5388e76a3bf679ff65 upstream.

In order to support the 1024x600 panel on Yeeloong Loongson MIPS
laptop, the original 1024x768-16 table was modified to 1024x600-16,
without leaving the original. It causes problem on x86 laptop as
the 1024x768-16 support was still claimed but not working.

Fix it by introducing the 1024x768-16 mode.

Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Tested-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: Teddy Wang &lt;teddy.wang@siliconmotion.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;  # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>fbdev: sm712fb: fix crashes during framebuffer writes by correctly mapping VRAM</title>
<updated>2019-06-11T10:23:48+00:00</updated>
<author>
<name>Yifeng Li</name>
<email>tomli@tomli.me</email>
</author>
<published>2019-04-01T15:46:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ebfadb510e3cd953425f5a29114cc7be8e5ac069'/>
<id>ebfadb510e3cd953425f5a29114cc7be8e5ac069</id>
<content type='text'>
commit 9e0e59993df0601cddb95c4f6c61aa3d5e753c00 upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), running fbtest or X
will crash the machine instantly, because the VRAM/framebuffer is not
mapped correctly.

On SM712, the framebuffer starts at the beginning of address space, but
SM720's framebuffer starts at the 1 MiB offset from the beginning. However,
sm712fb fails to take this into account, as a result, writing to the
framebuffer will destroy all the registers and kill the system immediately.
Another problem is the driver assumes 8 MiB of VRAM for SM720, but some
SM720 system, such as this IBM Thinkpad, only has 4 MiB of VRAM.

Fix this problem by removing the hardcoded VRAM size, adding a function to
query the amount of VRAM from register MCR76 on SM720, and adding proper
framebuffer offset.

Please note that the memory map may have additional problems on Big-Endian
system, which is not available for testing by myself. But I highly suspect
that the original code is also broken on Big-Endian machines for SM720, so
at least we are not making the problem worse. More, the driver also assumed
SM710/SM712 has 4 MiB of VRAM, but it has a 2 MiB version as well, and used
in earlier laptops, such as IBM Thinkpad 240X, the driver would probably
crash on them. I've never seen one of those machines and cannot fix it, but
I have documented these problems in the comments.

Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Tested-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: Teddy Wang &lt;teddy.wang@siliconmotion.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;  # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9e0e59993df0601cddb95c4f6c61aa3d5e753c00 upstream.

On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), running fbtest or X
will crash the machine instantly, because the VRAM/framebuffer is not
mapped correctly.

On SM712, the framebuffer starts at the beginning of address space, but
SM720's framebuffer starts at the 1 MiB offset from the beginning. However,
sm712fb fails to take this into account, as a result, writing to the
framebuffer will destroy all the registers and kill the system immediately.
Another problem is the driver assumes 8 MiB of VRAM for SM720, but some
SM720 system, such as this IBM Thinkpad, only has 4 MiB of VRAM.

Fix this problem by removing the hardcoded VRAM size, adding a function to
query the amount of VRAM from register MCR76 on SM720, and adding proper
framebuffer offset.

Please note that the memory map may have additional problems on Big-Endian
system, which is not available for testing by myself. But I highly suspect
that the original code is also broken on Big-Endian machines for SM720, so
at least we are not making the problem worse. More, the driver also assumed
SM710/SM712 has 4 MiB of VRAM, but it has a 2 MiB version as well, and used
in earlier laptops, such as IBM Thinkpad 240X, the driver would probably
crash on them. I've never seen one of those machines and cannot fix it, but
I have documented these problems in the comments.

Signed-off-by: Yifeng Li &lt;tomli@tomli.me&gt;
Tested-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&gt;
Cc: Teddy Wang &lt;teddy.wang@siliconmotion.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;  # v4.4+
Signed-off-by: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
