8795 Commits

Author SHA1 Message Date
Javier Martinez Canillas
13d28e0c79 fbdev: Disable sysfb device registration when removing conflicting FBs
[ Upstream commit ee7a69aa38d87a3bbced7b8245c732c05ed0c6ec ]

The platform devices registered by sysfb match with firmware-based DRM or
fbdev drivers, that are used to have early graphics using a framebuffer
provided by the system firmware.

DRM or fbdev drivers later are probed and remove conflicting framebuffers,
leading to these platform devices for generic drivers to be unregistered.

But the current solution has a race, since the sysfb_init() function could
be called after a DRM or fbdev driver is probed and request to unregister
the devices for drivers with conflicting framebuffes.

To prevent this, disable any future sysfb platform device registration by
calling sysfb_disable(), if a driver requests to remove the conflicting
framebuffers.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220607182338.344270-4-javierm@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-21 21:24:35 +02:00
Helge Deller
9c9e44bb3d fbcon: Prevent that screen size is smaller than font size
commit e64242caef18b4a5840b0e7a9bff37abd4f4f933 upstream.

We need to prevent that users configure a screen size which is smaller than the
currently selected font size. Otherwise rendering chars on the screen will
access memory outside the graphics memory region.

This patch adds a new function fbcon_modechange_possible() which
implements this check and which later may be extended with other checks
if necessary.  The new function is called from the FBIOPUT_VSCREENINFO
ioctl handler in fbmem.c, which will return -EINVAL if userspace asked
for a too small screen size.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-12 16:35:09 +02:00
Helge Deller
6886327780 fbcon: Disallow setting font bigger than screen size
commit 65a01e601dbba8b7a51a2677811f70f783766682 upstream.

Prevent that users set a font size which is bigger than the physical screen.
It's unlikely this may happen (because screens are usually much larger than the
fonts and each font char is limited to 32x32 pixels), but it may happen on
smaller screens/LCD displays.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-12 16:35:09 +02:00
Helge Deller
738d06ef99 fbmem: Check virtual screen sizes in fb_set_var()
commit 6c11df58fd1ac0aefcb3b227f72769272b939e56 upstream.

Verify that the fbdev or drm driver correctly adjusted the virtual
screen sizes. On failure report the failing driver and reject the screen
size change.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-12 16:35:09 +02:00
Guiling Deng
989b2c4032 fbdev: fbmem: Fix logo center image dx issue
commit 955f04766d4e6eb94bf3baa539e096808c74ebfb upstream.

Image.dx gets wrong value because of missing '()'.

If xres == logo->width and n == 1, image.dx = -16.

Signed-off-by: Guiling Deng <greens9@163.com>
Fixes: 3d8b1933eb1c ("fbdev: fbmem: add config option to center the bootup logo")
Cc: stable@vger.kernel.org # v5.0+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-12 16:35:09 +02:00
Helge Deller
cb4d52085c parisc/stifb: Fix fb_is_primary_device() only available with CONFIG_FB_STI
commit 1d0811b03eb30b2f0793acaa96c6ce90b8b9c87a upstream.

Fix this build error noticed by the kernel test robot:

drivers/video/console/sticore.c:1132:5: error: redefinition of 'fb_is_primary_device'
 arch/parisc/include/asm/fb.h:18:19: note: previous definition of 'fb_is_primary_device'

Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: kernel test robot <lkp@intel.com>
Cc: stable@vger.kernel.org   # v5.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-29 09:03:29 +02:00
Yang Yingliang
ca02b96755 video: fbdev: pxa3xx-gcu: release the resources correctly in pxa3xx_gcu_probe/remove()
[ Upstream commit d87ad457f7e1b8d2492ca5b1531eb35030a1cc8f ]

In pxa3xx_gcu_probe(), the sequence of error lable is wrong, it will
leads some resource leaked, so adjust the sequence to handle the error
correctly, and if pxa3xx_gcu_add_buffer() fails, pxa3xx_gcu_free_buffers()
need be called.
In pxa3xx_gcu_remove(), add missing clk_disable_unpreprare().

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:36:15 +02:00
Saurabh Sengar
e4cf9982ff video: fbdev: hyperv_fb: Allow resolutions with size > 64 MB for Gen1
[ Upstream commit c4b4d7047f16a8d138ce76da65faefb7165736f2 ]

This patch fixes a bug where GEN1 VMs doesn't allow resolutions greater
than 64 MB size (eg 7680x4320). Unnecessary PCI check limits Gen1 VRAM
to legacy PCI BAR size only (ie 64MB). Thus any, resolution requesting
greater then 64MB (eg 7680x4320) would fail. MMIO region assigning this
memory shouldn't be limited by PCI bar size.

Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:36:15 +02:00
Javier Martinez Canillas
0fac5f8fb1 video: fbdev: vesafb: Fix a use-after-free due early fb_info cleanup
[ Upstream commit acde4003efc16480375543638484d8f13f2e99a3 ]

Commit b3c9a924aab6 ("fbdev: vesafb: Cleanup fb_info in .fb_destroy rather
than .remove") fixed a use-after-free error due the vesafb driver freeing
the fb_info in the .remove handler instead of doing it in .fb_destroy.

This can happen if the .fb_destroy callback is executed after the .remove
callback, since the former tries to access a pointer freed by the latter.

But that change didn't take into account that another possible scenario is
that .fb_destroy is called before the .remove callback. For example, if no
process has the fbdev chardev opened by the time the driver is removed.

If that's the case, fb_info will be freed when unregister_framebuffer() is
called, making the fb_info pointer accessed in vesafb_remove() after that
to no longer be valid.

To prevent that, move the expression containing the info->par to happen
before the unregister_framebuffer() function call.

Fixes: b3c9a924aab6 ("fbdev: vesafb: Cleanup fb_info in .fb_destroy rather than .remove")
Reported-by: Pascal Ernster <dri-devel@hardfalcon.net>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Pascal Ernster <dri-devel@hardfalcon.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:23:16 +02:00
Miaoqian Lin
f2dfb4ab88 video: fbdev: clcdfb: Fix refcount leak in clcdfb_of_vram_setup
[ Upstream commit b23789a59fa6f00e98a319291819f91fbba0deb8 ]

of_parse_phandle() returns a node pointer with refcount incremented, we should
use of_node_put() on it when not need anymore.  Add missing of_node_put() to
avoid refcount leak.

Fixes: d10715be03bd ("video: ARM CLCD: Add DT support")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:23:15 +02:00
Daniel Vetter
0781b56404 fbcon: Consistently protect deferred_takeover with console_lock()
[ Upstream commit 43553559121ca90965b572cf8a1d6d0fd618b449 ]

This shouldn't be a problem in practice since until we've actually
taken over the console there's nothing we've registered with the
console/vt subsystem, so the exit/unbind path that check this can't
do the wrong thing. But it's confusing, so fix it by moving it a tad
later.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Du Cheng <ducheng2@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Claudio Suarez <cssk@net-c.es>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220405210335.3434130-14-daniel.vetter@ffwll.ch
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:22:31 +02:00
Helge Deller
e639a66ca9 parisc/stifb: Keep track of hardware path of graphics card
commit b046f984814af7985f444150ec28716d42d00d9a upstream.

Keep the pa_path (hardware path) of the graphics card in sti_struct and use
this info to give more useful info which card is currently being used.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org   # v5.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-09 10:22:26 +02:00
Helge Deller
8b8fe78cae parisc/stifb: Implement fb_is_primary_device()
commit cf936af790a3ef5f41ff687ec91bfbffee141278 upstream.

Implement fb_is_primary_device() function, so that fbcon detects if this
framebuffer belongs to the default graphics card which was used to start
the system.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org   # v5.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-09 10:22:26 +02:00
Daniel Vetter
4f631f9f9d fbdev: Prevent possible use-after-free in fb_release()
[ Upstream commit 89bfd4017e58faaf70411555e7f508495114e90b ]

Most fbdev drivers have issues with the fb_info lifetime, because call to
framebuffer_release() from their driver's .remove callback, rather than
doing from fbops.fb_destroy callback.

Doing that will destroy the fb_info too early, while references to it may
still exist, leading to a use-after-free error.

To prevent this, check the fb_info reference counter when attempting to
kfree the data structure in framebuffer_release(). That will leak it but
at least will prevent the mentioned error.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220505220413.365977-1-javierm@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-25 09:57:35 +02:00
Javier Martinez Canillas
92dc6278de Revert "fbdev: Make fb_release() return -ENODEV if fbdev was unregistered"
[ Upstream commit 135332f34ba2662bc1e32b5c612e06a8cc41a053 ]

This reverts commit aafa025c76dcc7d1a8c8f0bdefcbe4eb480b2f6a. That commit
attempted to fix a NULL pointer dereference, caused by the struct fb_info
associated with a framebuffer device to not longer be valid when the file
descriptor was closed.

The issue was exposed by commit 27599aacbaef ("fbdev: Hot-unplug firmware
fb devices on forced removal"), which added a new path that goes through
the struct device removal instead of directly unregistering the fb.

Most fbdev drivers have issues with the fb_info lifetime, because call to
framebuffer_release() from their driver's .remove callback, rather than
doing from fbops.fb_destroy callback. This meant that due to this switch,
the fb_info was now destroyed too early, while references still existed,
while before it was simply leaked.

The patch we're reverting here reinstated that leak, hence "fixed" the
regression. But the proper solution is to fix the drivers to not release
the fb_info too soon.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220504115917.758787-1-javierm@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-25 09:57:35 +02:00
Javier Martinez Canillas
ef090cd44d fbdev: efifb: Fix a use-after-free due early fb_info cleanup
[ Upstream commit 1b5853dfab7fdde450f00f145327342238135c8a ]

Commit d258d00fb9c7 ("fbdev: efifb: Cleanup fb_info in .fb_destroy rather
than .remove") attempted to fix a use-after-free error due driver freeing
the fb_info in the .remove handler instead of doing it in .fb_destroy.

But ironically that change introduced yet another use-after-free since the
fb_info was still used after the free.

This should fix for good by freeing the fb_info at the end of the handler.

Fixes: d258d00fb9c7 ("fbdev: efifb: Cleanup fb_info in .fb_destroy rather than .remove")
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reported-by: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Reviewed-by: Thomas Zimmermann <tzimemrmann@suse.de>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220506132225.588379-1-javierm@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 10:26:49 +02:00
Javier Martinez Canillas
f94aa46efa fbdev: vesafb: Cleanup fb_info in .fb_destroy rather than .remove
[ Upstream commit b3c9a924aab61adbc29df110006aa03afe1a78ba ]

The driver is calling framebuffer_release() in its .remove callback, but
this will cause the struct fb_info to be freed too early. Since it could
be that a reference is still hold to it if user-space opened the fbdev.

This would lead to a use-after-free error if the framebuffer device was
unregistered but later a user-space process tries to close the fbdev fd.

To prevent this, move the framebuffer_release() call to fb_ops.fb_destroy
instead of doing it in the driver's .remove callback.

Strictly speaking, the code flow in the driver is still wrong because all
the hardware cleanupd (i.e: iounmap) should be done in .remove while the
software cleanup (i.e: releasing the framebuffer) should be done in the
.fb_destroy handler. But this at least makes to match the behavior before
commit 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal").

Fixes: 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal")
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220505220631.366371-1-javierm@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 10:26:48 +02:00
Javier Martinez Canillas
cd3c8abbdc fbdev: efifb: Cleanup fb_info in .fb_destroy rather than .remove
[ Upstream commit d258d00fb9c7c0cdf9d10c1ded84f10339d2d349 ]

The driver is calling framebuffer_release() in its .remove callback, but
this will cause the struct fb_info to be freed too early. Since it could
be that a reference is still hold to it if user-space opened the fbdev.

This would lead to a use-after-free error if the framebuffer device was
unregistered but later a user-space process tries to close the fbdev fd.

To prevent this, move the framebuffer_release() call to fb_ops.fb_destroy
instead of doing it in the driver's .remove callback.

Strictly speaking, the code flow in the driver is still wrong because all
the hardware cleanupd (i.e: iounmap) should be done in .remove while the
software cleanup (i.e: releasing the framebuffer) should be done in the
.fb_destroy handler. But this at least makes to match the behavior before
commit 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal").

Fixes: 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal")
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220505220540.366218-1-javierm@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 10:26:48 +02:00
Javier Martinez Canillas
02eef429bf fbdev: simplefb: Cleanup fb_info in .fb_destroy rather than .remove
[ Upstream commit 666b90b3ce9e4aac1e1deba266c3a230fb3913b0 ]

The driver is calling framebuffer_release() in its .remove callback, but
this will cause the struct fb_info to be freed too early. Since it could
be that a reference is still hold to it if user-space opened the fbdev.

This would lead to a use-after-free error if the framebuffer device was
unregistered but later a user-space process tries to close the fbdev fd.

To prevent this, move the framebuffer_release() call to fb_ops.fb_destroy
instead of doing it in the driver's .remove callback.

Strictly speaking, the code flow in the driver is still wrong because all
the hardware cleanupd (i.e: iounmap) should be done in .remove while the
software cleanup (i.e: releasing the framebuffer) should be done in the
.fb_destroy handler. But this at least makes to match the behavior before
commit 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal").

Fixes: 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal")
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220505220456.366090-1-javierm@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 10:26:48 +02:00
Javier Martinez Canillas
161568b749 fbdev: Make fb_release() return -ENODEV if fbdev was unregistered
[ Upstream commit aafa025c76dcc7d1a8c8f0bdefcbe4eb480b2f6a ]

A reference to the framebuffer device struct fb_info is stored in the file
private data, but this reference could no longer be valid and must not be
accessed directly. Instead, the file_fb_info() accessor function must be
used since it does sanity checking to make sure that the fb_info is valid.

This can happen for example if the registered framebuffer device is for a
driver that just uses a framebuffer provided by the system firmware. In
that case, the fbdev core would unregister the framebuffer device when a
real video driver is probed and ask to remove conflicting framebuffers.

The bug has been present for a long time but commit 27599aacbaef ("fbdev:
Hot-unplug firmware fb devices on forced removal") unmasked it since the
fbdev core started unregistering the framebuffers' devices associated.

Fixes: 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal")
Reported-by: Maxime Ripard <maxime@cerno.tech>
Reported-by: Junxiao Chang <junxiao.chang@intel.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220502135014.377945-1-javierm@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-12 12:30:22 +02:00
Pavel Skripkin
4df1584738 video: fbdev: udlfb: properly check endpoint type
[ Upstream commit aaf7dbe07385e0b8deb7237eca2a79926bbc7091 ]

syzbot reported warning in usb_submit_urb, which is caused by wrong
endpoint type.

This driver uses out bulk endpoint for communication, so
let's check if this endpoint is present and bail out early if not.

Fail log:

usb 1-1: BOGUS urb xfer, pipe 3 != type 1
WARNING: CPU: 0 PID: 4822 at drivers/usb/core/urb.c:493 usb_submit_urb+0xd27/0x1540 drivers/usb/core/urb.c:493
Modules linked in:
CPU: 0 PID: 4822 Comm: kworker/0:3 Tainted: G        W         5.13.0-syzkaller #0
...
Workqueue: usb_hub_wq hub_event
RIP: 0010:usb_submit_urb+0xd27/0x1540 drivers/usb/core/urb.c:493
...
Call Trace:
 dlfb_submit_urb+0x89/0x160 drivers/video/fbdev/udlfb.c:1969
 dlfb_set_video_mode+0x21f0/0x2950 drivers/video/fbdev/udlfb.c:315
 dlfb_ops_set_par+0x2a3/0x840 drivers/video/fbdev/udlfb.c:1110
 dlfb_usb_probe.cold+0x113e/0x1f4a drivers/video/fbdev/udlfb.c:1732
 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396

Fixes: 88e58b1a42f8 ("Staging: add udlfb driver")
Reported-and-tested-by: syzbot+53ce4a4246d0fe0fee34@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-09 09:14:31 +02:00
Thomas Zimmermann
2388f826cd fbdev: Fix unregistering of framebuffers without device
commit 0f525289ff0ddeb380813bd81e0f9bdaaa1c9078 upstream.

OF framebuffers do not have an underlying device in the Linux
device hierarchy. Do a regular unregister call instead of hot
unplugging such a non-existing device. Fixes a NULL dereference.
An example error message on ppc64le is shown below.

  BUG: Kernel NULL pointer dereference on read at 0x00000060
  Faulting instruction address: 0xc00000000080dfa4
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
  [...]
  CPU: 2 PID: 139 Comm: systemd-udevd Not tainted 5.17.0-ae085d7f9365 #1
  NIP:  c00000000080dfa4 LR: c00000000080df9c CTR: c000000000797430
  REGS: c000000004132fe0 TRAP: 0300   Not tainted  (5.17.0-ae085d7f9365)
  MSR:  8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE>  CR: 28228282  XER: 20000000
  CFAR: c00000000000c80c DAR: 0000000000000060 DSISR: 40000000 IRQMASK: 0
  GPR00: c00000000080df9c c000000004133280 c00000000169d200 0000000000000029
  GPR04: 00000000ffffefff c000000004132f90 c000000004132f88 0000000000000000
  GPR08: c0000000015658f8 c0000000015cd200 c0000000014f57d0 0000000048228283
  GPR12: 0000000000000000 c00000003fffe300 0000000020000000 0000000000000000
  GPR16: 0000000000000000 0000000113fc4a40 0000000000000005 0000000113fcfb80
  GPR20: 000001000f7283b0 0000000000000000 c000000000e4a588 c000000000e4a5b0
  GPR24: 0000000000000001 00000000000a0000 c008000000db0168 c0000000021f6ec0
  GPR28: c0000000016d65a8 c000000004b36460 0000000000000000 c0000000016d64b0
  NIP [c00000000080dfa4] do_remove_conflicting_framebuffers+0x184/0x1d0
  [c000000004133280] [c00000000080df9c] do_remove_conflicting_framebuffers+0x17c/0x1d0 (unreliable)
  [c000000004133350] [c00000000080e4d0] remove_conflicting_framebuffers+0x60/0x150
  [c0000000041333a0] [c00000000080e6f4] remove_conflicting_pci_framebuffers+0x134/0x1b0
  [c000000004133450] [c008000000e70438] drm_aperture_remove_conflicting_pci_framebuffers+0x90/0x100 [drm]
  [c000000004133490] [c008000000da0ce4] bochs_pci_probe+0x6c/0xa64 [bochs]
  [...]
  [c000000004133db0] [c00000000002aaa0] system_call_exception+0x170/0x2d0
  [c000000004133e10] [c00000000000c3cc] system_call_common+0xec/0x250

The bug [1] was introduced by commit 27599aacbaef ("fbdev: Hot-unplug
firmware fb devices on forced removal"). Most firmware framebuffers
have an underlying platform device, which can be hot-unplugged
before loading the native graphics driver. OF framebuffers do not
(yet) have that device. Fix the code by unregistering the framebuffer
as before without a hot unplug.

Tested with 5.17 on qemu ppc64le emulation.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal")
Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Cc: Zack Rusin <zackr@vmware.com>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: stable@vger.kernel.org # v5.11+
Cc: Helge Deller <deller@gmx.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Zheyu Ma <zheyuma97@gmail.com>
Cc: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Link: https://lore.kernel.org/all/YkHXO6LGHAN0p1pq@debian/ # [1]
Link: https://patchwork.freedesktop.org/patch/msgid/20220404194402.29974-1-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-13 20:59:24 +02:00
Zheyu Ma
eae90015d1 video: fbdev: sm712fb: Fix crash in smtcfb_write()
[ Upstream commit 4f01d09b2bbfbcb47b3eb305560a7f4857a32260 ]

When the sm712fb driver writes three bytes to the framebuffer, the
driver will crash:

    BUG: unable to handle page fault for address: ffffc90001ffffff
    RIP: 0010:smtcfb_write+0x454/0x5b0
    Call Trace:
     vfs_write+0x291/0xd60
     ? do_sys_openat2+0x27d/0x350
     ? __fget_light+0x54/0x340
     ksys_write+0xce/0x190
     do_syscall_64+0x43/0x90
     entry_SYSCALL_64_after_hwframe+0x44/0xae

Fix it by removing the open-coded endianness fixup-code.

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:24:02 +02:00
Jing Yao
2d5c47df8e video: fbdev: udlfb: replace snprintf in show functions with sysfs_emit
[ Upstream commit 81a998288956d09d7a7a2303d47e4d60ad55c401 ]

Use sysfs_emit instead of scnprintf, snprintf or sprintf.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Jing Yao <yao.jing2@zte.com.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:24:01 +02:00
Jing Yao
e7f5b1c569 video: fbdev: omapfb: panel-tpo-td043mtea1: Use sysfs_emit() instead of snprintf()
[ Upstream commit c07a039cbb96748f54c02995bae8131cc9a73b0a ]

Use sysfs_emit instead of scnprintf, snprintf or sprintf.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Jing Yao <yao.jing2@zte.com.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:24:01 +02:00
Jing Yao
509bc99aba video: fbdev: omapfb: panel-dsi-cm: Use sysfs_emit() instead of snprintf()
[ Upstream commit f63658a59c3d439c8ad7b290f8ec270980e0f384 ]

Use sysfs_emit instead of scnprintf, snprintf or sprintf.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Jing Yao <yao.jing2@zte.com.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:24:01 +02:00
Yang Guang
5217960188 video: fbdev: omapfb: acx565akm: replace snprintf with sysfs_emit
[ Upstream commit 24565bc4115961db7ee64fcc7ad2a7437c0d0a49 ]

coccinelle report:
./drivers/video/fbdev/omap2/omapfb/displays/panel-sony-acx565akm.c:
479:9-17: WARNING: use scnprintf or sprintf

Use sysfs_emit instead of scnprintf or sprintf makes more sense.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:24:00 +02:00
George Kennedy
6fe23ff94e video: fbdev: cirrusfb: check pixclock to avoid divide by zero
[ Upstream commit 5c6f402bdcf9e7239c6bc7087eda71ac99b31379 ]

Do a sanity check on pixclock value to avoid divide by zero.

If the pixclock value is zero, the cirrusfb driver will round up
pixclock to get the derived frequency as close to maxclock as
possible.

Syzkaller reported a divide error in cirrusfb_check_pixclock.

divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 PID: 14938 Comm: cirrusfb_test Not tainted 5.15.0-rc6 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2
RIP: 0010:cirrusfb_check_var+0x6f1/0x1260

Call Trace:
 fb_set_var+0x398/0xf90
 do_fb_ioctl+0x4b8/0x6f0
 fb_ioctl+0xeb/0x130
 __x64_sys_ioctl+0x19d/0x220
 do_syscall_64+0x3a/0x80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:24:00 +02:00
Evgeny Novikov
9522e11e86 video: fbdev: w100fb: Reset global state
[ Upstream commit 8738ddcac644964ae128ccd3d80d48773c8d528e ]

w100fb_probe() did not reset the global state to its initial state. This
can result in invocation of iounmap() even when there was not the
appropriate successful call of ioremap(). For instance, this may be the
case if first probe fails after two successful ioremap() while second
probe fails when first ioremap() fails. The similar issue is with
w100fb_remove(). The patch fixes both bugs.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Evgeny Novikov <novikov@ispras.ru>
Co-developed-by: Kirill Shilimanov <kirill.shilimanov@huawei.com>
Signed-off-by: Kirill Shilimanov <kirill.shilimanov@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:59 +02:00
Tim Gardner
9ff2f7294a video: fbdev: nvidiafb: Use strscpy() to prevent buffer overflow
[ Upstream commit 37a1a2e6eeeb101285cd34e12e48a881524701aa ]

Coverity complains of a possible buffer overflow. However,
given the 'static' scope of nvidia_setup_i2c_bus() it looks
like that can't happen after examiniing the call sites.

CID 19036 (#1 of 1): Copy into fixed size buffer (STRING_OVERFLOW)
1. fixed_size_dest: You might overrun the 48-character fixed-size string
  chan->adapter.name by copying name without checking the length.
2. parameter_as_source: Note: This defect has an elevated risk because the
  source argument is a parameter of the current function.
 89        strcpy(chan->adapter.name, name);

Fix this warning by using strscpy() which will silence the warning and
prevent any future buffer overflows should the names used to identify the
channel become much longer.

Cc: Antonino Daplas <adaplas@gmail.com>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:59 +02:00
Miaoqian Lin
a41fc6d02d video: fbdev: omapfb: Add missing of_node_put() in dvic_probe_of
[ Upstream commit a58c22cfbbf62fefca090334bbd35fd132e92a23 ]

The device_node pointer is returned by of_parse_phandle()  with refcount
incremented. We should use of_node_put() on it when done.

Fixes: f76ee892a99e ("omapfb: copy omapdss & displays for omapfb")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:21 +02:00
Dan Carpenter
c3364cbc37 video: fbdev: fbcvt.c: fix printing in fb_cvt_print_name()
[ Upstream commit 78482af095abd9f4f29f1aa3fe575d25c6ae3028 ]

This code has two bugs:
1) "cnt" is 255 but the size of the buffer is 256 so the last byte is
   not used.
2) If we try to print more than 255 characters then "cnt" will be
   negative and that will trigger a WARN() in snprintf(). The fix for
   this is to use scnprintf() instead of snprintf().

We can re-write this code to be cleaner:
1) Rename "offset" to "off" because that's shorter.
2) Get rid of the "cnt" variable and just use "size - off" directly.
3) Get rid of the "read" variable and just increment "off" directly.

Fixes: 96fe6a2109db ("fbdev: Add VESA Coordinated Video Timings (CVT) support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:15 +02:00
Dan Carpenter
f3ef254c84 video: fbdev: atmel_lcdfb: fix an error code in atmel_lcdfb_probe()
[ Upstream commit fee5c1e4b789e41719af9fee0e2dd397cd31988f ]

If "sinfo->config" is not found, then return -ENODEV.  Don't
return success.

Fixes: b985172b328a ("video: atmel_lcdfb: add device tree suport")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:14 +02:00
Wang Hai
c420b540db video: fbdev: smscufx: Fix null-ptr-deref in ufx_usb_probe()
[ Upstream commit 1791f487f877a9e83d81c8677bd3e7b259e7cb27 ]

I got a null-ptr-deref report:

BUG: kernel NULL pointer dereference, address: 0000000000000000
...
RIP: 0010:fb_destroy_modelist+0x38/0x100
...
Call Trace:
 ufx_usb_probe.cold+0x2b5/0xac1 [smscufx]
 usb_probe_interface+0x1aa/0x3c0 [usbcore]
 really_probe+0x167/0x460
...
 ret_from_fork+0x1f/0x30

If fb_alloc_cmap() fails in ufx_usb_probe(), fb_destroy_modelist() will
be called to destroy modelist in the error handling path. But modelist
has not been initialized yet, so it will result in null-ptr-deref.

Initialize modelist before calling fb_alloc_cmap() to fix this bug.

Fixes: 3c8a63e22a08 ("Add support for SMSC UFX6000/7000 USB display adapters")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:14 +02:00
YueHaibing
24cfeb4661 video: fbdev: controlfb: Fix COMPILE_TEST build
[ Upstream commit 567e44fb51b4f909ae58038a7301352eecea8426 ]

If PPC_BOOK3S, PPC_PMAC and PPC32 is n, COMPILE_TEST build fails:

drivers/video/fbdev/controlfb.c:70:0: error: "pgprot_cached_wthru" redefined [-Werror]
 #define pgprot_cached_wthru(prot) (prot)

In file included from ./arch/powerpc/include/asm/pgtable.h:20:0,
                 from ./include/linux/pgtable.h:6,
                 from ./include/linux/mm.h:33,
                 from drivers/video/fbdev/controlfb.c:37:
./arch/powerpc/include/asm/nohash/pgtable.h:243:0: note: this is the location of the previous definition
 #define pgprot_cached_wthru(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \

Fixes: a07a63b0e24d ("video: fbdev: controlfb: add COMPILE_TEST support")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:14 +02:00
Z. Liu
02684dd833 video: fbdev: matroxfb: set maxvram of vbG200eW to the same as vbG200 to avoid black screen
[ Upstream commit 62d89a7d49afe46e6b9bbe9e23b004ad848dbde4 ]

Start from commit 11be60bd66d54 "matroxfb: add Matrox MGA-G200eW board
support", when maxvram is 0x800000, monitor become black w/ error message
said: "The current input timing is not supported by the monitor display.
Please change your input timing to 1920x1080@60Hz ...".

Fixes: 11be60bd66d5 ("matroxfb: add Matrox MGA-G200eW board support")
Signed-off-by: Z. Liu <liuzx@knownsec.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:14 +02:00
Michael Schmitz
677a5f6c81 video: fbdev: atari: Atari 2 bpp (STe) palette bugfix
commit c8be5edbd36ceed2ff3d6b8f8e40643c3f396ea3 upstream.

The code to set the shifter STe palette registers has a long
standing operator precedence bug, manifesting as colors set
on a 2 bits per pixel frame buffer coming up with a distinctive
blue tint.

Add parentheses around the calculation of the per-color palette
data before shifting those into their respective bit field position.

This bug goes back a long way (2.4 days at the very least) so there
won't be a Fixes: tag.

Tested on ARAnyM as well on Falcon030 hardware.

Cc: stable@vger.kernel.org
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/all/CAMuHMdU3ievhXxKR_xi_v3aumnYW7UNUO6qMdhgfyWTyVSsCkQ@mail.gmail.com
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-08 14:23:00 +02:00
Helge Deller
46cdbff26c video: fbdev: sm712fb: Fix crash in smtcfb_read()
commit bd771cf5c4254511cc4abb88f3dab3bd58bdf8e8 upstream.

Zheyu Ma reported this crash in the sm712fb driver when reading
three bytes from the framebuffer:

 BUG: unable to handle page fault for address: ffffc90001ffffff
 RIP: 0010:smtcfb_read+0x230/0x3e0
 Call Trace:
  vfs_read+0x198/0xa00
  ? do_sys_openat2+0x27d/0x350
  ? __fget_light+0x54/0x340
  ksys_read+0xce/0x190
  do_syscall_64+0x43/0x90

Fix it by removing the open-coded endianess fixup-code and
by moving the pointer post decrement out the fb_readl() function.

Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: Zheyu Ma <zheyuma97@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-08 14:23:00 +02:00
Thomas Zimmermann
c894ac4478 fbdev: Hot-unplug firmware fb devices on forced removal
commit 27599aacbaefcbf2af7b06b0029459bbf682000d upstream.

Hot-unplug all firmware-framebuffer devices as part of removing
them via remove_conflicting_framebuffers() et al. Releases all
memory regions to be acquired by native drivers.

Firmware, such as EFI, install a framebuffer while posting the
computer. After removing the firmware-framebuffer device from fbdev,
a native driver takes over the hardware and the firmware framebuffer
becomes invalid.

Firmware-framebuffer drivers, specifically simplefb, don't release
their device from Linux' device hierarchy. It still owns the firmware
framebuffer and blocks the native drivers from loading. This has been
observed in the vmwgfx driver. [1]

Initiating a device removal (i.e., hot unplug) as part of
remove_conflicting_framebuffers() removes the underlying device and
returns the memory range to the system.

[1] https://lore.kernel.org/dri-devel/20220117180359.18114-1-zack@kde.org/

v2:
	* rename variable 'dev' to 'device' (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reported-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
CC: stable@vger.kernel.org # v5.11+
Link: https://patchwork.freedesktop.org/patch/msgid/20220125091222.21457-2-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-08 14:22:59 +02:00
Helge Deller
3523167d66 fbcon: Avoid 'cap' set but not used warning
[ Upstream commit 50b10528aad568c95f772039d4b3093b4aea7439 ]

Fix this kernel test robot warning:

  drivers/video/fbdev/core/fbcon.c: In function 'fbcon_init':
  drivers/video/fbdev/core/fbcon.c:1028:6: warning: variable 'cap' set but not used [-Wunused-but-set-variable]

The cap variable is only used when CONFIG_FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION
is enabled. Drop the temporary variable and use info->flags instead.

Fixes: 87ab9f6b7417 ("Revert "fbcon: Disable accelerated scrolling")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/YgFB4xqI+As196FR@p100
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-16 12:56:27 +01:00
Helge Deller
778283dc28 fbcon: Add option to enable legacy hardware acceleration
commit a3f781a9d6114c1d1e01defb7aa234dec45d2a5f upstream.

Add a config option CONFIG_FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION to
enable bitblt and fillrect hardware acceleration in the framebuffer
console. If disabled, such acceleration will not be used, even if it is
supported by the graphics hardware driver.

If you plan to use DRM as your main graphics output system, you should
disable this option since it will prevent compiling in code which isn't
used later on when DRM takes over.

For all other configurations, e.g. if none of your graphic cards support
DRM (yet), DRM isn't available for your architecture, or you can't be
sure that the graphic card in the target system will support DRM, you
most likely want to enable this option.

In the non-accelerated case (e.g. when DRM is used), the inlined
fb_scrollmode() function is hardcoded to return SCROLL_REDRAW and as such the
compiler is able to optimize much unneccesary code away.

In this v3 patch version I additionally changed the GETVYRES() and GETVXRES()
macros to take a pointer to the fbcon_display struct. This fixes the build when
console rotation is enabled and helps the compiler again to optimize out code.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220202135531.92183-4-deller@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-08 18:34:06 +01:00
Helge Deller
2a2629db42 Revert "fbcon: Disable accelerated scrolling"
commit 87ab9f6b7417349aa197a6c7098d4fdd4beebb74 upstream.

This reverts commit 39aead8373b3c20bb5965c024dfb51a94e526151.

Revert the first (of 2) commits which disabled scrolling acceleration in
fbcon/fbdev.  It introduced a regression for fbdev-supported graphic cards
because of the performance penalty by doing screen scrolling by software
instead of using the existing graphic card 2D hardware acceleration.

Console scrolling acceleration was disabled by dropping code which
checked at runtime the driver hardware capabilities for the
BINFO_HWACCEL_COPYAREA or FBINFO_HWACCEL_FILLRECT flags and if set, it
enabled scrollmode SCROLL_MOVE which uses hardware acceleration to move
screen contents.  After dropping those checks scrollmode was hard-wired
to SCROLL_REDRAW instead, which forces all graphic cards to redraw every
character at the new screen position when scrolling.

This change effectively disabled all hardware-based scrolling acceleration for
ALL drivers, because now all kind of 2D hardware acceleration (bitblt,
fillrect) in the drivers isn't used any longer.

The original commit message mentions that only 3 DRM drivers (nouveau, omapdrm
and gma500) used hardware acceleration in the past and thus code for checking
and using scrolling acceleration is obsolete.

This statement is NOT TRUE, because beside the DRM drivers there are around 35
other fbdev drivers which depend on fbdev/fbcon and still provide hardware
acceleration for fbdev/fbcon.

The original commit message also states that syzbot found lots of bugs in fbcon
and thus it's "often the solution to just delete code and remove features".
This is true, and the bugs - which actually affected all users of fbcon,
including DRM - were fixed, or code was dropped like e.g. the support for
software scrollback in vgacon (commit 973c096f6a85).

So to further analyze which bugs were found by syzbot, I've looked through all
patches in drivers/video which were tagged with syzbot or syzkaller back to
year 2005. The vast majority fixed the reported issues on a higher level, e.g.
when screen is to be resized, or when font size is to be changed. The few ones
which touched driver code fixed a real driver bug, e.g. by adding a check.

But NONE of those patches touched code of either the SCROLL_MOVE or the
SCROLL_REDRAW case.

That means, there was no real reason why SCROLL_MOVE had to be ripped-out and
just SCROLL_REDRAW had to be used instead. The only reason I can imagine so far
was that SCROLL_MOVE wasn't used by DRM and as such it was assumed that it
could go away. That argument completely missed the fact that SCROLL_MOVE is
still heavily used by fbdev (non-DRM) drivers.

Some people mention that using memcpy() instead of the hardware acceleration is
pretty much the same speed. But that's not true, at least not for older graphic
cards and machines where we see speed decreases by factor 10 and more and thus
this change leads to console responsiveness way worse than before.

That's why the original commit is to be reverted. By reverting we
reintroduce hardware-based scrolling acceleration and fix the
performance regression for fbdev drivers.

There isn't any impact on DRM when reverting those patches.

Signed-off-by: Helge Deller <deller@gmx.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Sven Schnelle <svens@stackframe.org>
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220202135531.92183-3-deller@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-08 18:34:06 +01:00
Michael Kelley
d0a56e4ebc video: hyperv_fb: Fix validation of screen resolution
[ Upstream commit 9ff5549b1d1d3c3a9d71220d44bd246586160f1d ]

In the WIN10 version of the Synthetic Video protocol with Hyper-V,
Hyper-V reports a list of supported resolutions as part of the protocol
negotiation. The driver calculates the maximum width and height from
the list of resolutions, and uses those maximums to validate any screen
resolution specified in the video= option on the kernel boot line.

This method of validation is incorrect. For example, the list of
supported resolutions could contain 1600x1200 and 1920x1080, both of
which fit in an 8 Mbyte frame buffer.  But calculating the max width
and height yields 1920 and 1200, and 1920x1200 resolution does not fit
in an 8 Mbyte frame buffer.  Unfortunately, this resolution is accepted,
causing a kernel fault when the driver accesses memory outside the
frame buffer.

Instead, validate the specified screen resolution by calculating
its size, and comparing against the frame buffer size.  Delete the
code for calculating the max width and height from the list of
resolutions, since these max values have no use.  Also add the
frame buffer size to the info message to aid in understanding why
a resolution might be rejected.

Fixes: 67e7cdb4829d ("video: hyperv: hyperv_fb: Obtain screen resolution from Hyper-V host")
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://lore.kernel.org/r/1642360711-2335-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-01 17:27:12 +01:00
Marijn Suijten
7a4e6e0878 backlight: qcom-wled: Respect enabled-strings in set_brightness
[ Upstream commit ec961cf3241153e0f27d850f1bf0f172e7d27a21 ]

The hardware is capable of controlling any non-contiguous sequence of
LEDs specified in the DT using qcom,enabled-strings as u32
array, and this also follows from the DT-bindings documentation.  The
numbers specified in this array represent indices of the LED strings
that are to be enabled and disabled.

Its value is appropriately used to setup and enable string modules, but
completely disregarded in the set_brightness paths which only iterate
over the number of strings linearly.
Take an example where only string 2 is enabled with
qcom,enabled_strings=<2>: this string is appropriately enabled but
subsequent brightness changes would have only touched the zero'th
brightness register because num_strings is 1 here.  This is simply
addressed by looking up the string for this index in the enabled_strings
array just like the other codepaths that iterate over num_strings.

Likewise enabled_strings is now also used in the autodetection path for
consistent behaviour: when a list of strings is specified in DT only
those strings will be probed for autodetection, analogous to how the
number of strings that need to be probed is already bound by
qcom,num-strings.  After all autodetection uses the set_brightness
helpers to set an initial value, which could otherwise end up changing
brightness on a different set of strings.

Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3")
Fixes: 03b2b5e86986 ("backlight: qcom-wled: Add support for WLED4 peripheral")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-10-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 11:03:46 +01:00
Marijn Suijten
7abe05ef66 backlight: qcom-wled: Use cpu_to_le16 macro to perform conversion
[ Upstream commit 0a139358548968b2ff308257b4fbeec7badcc3e1 ]

The kernel already provides appropriate primitives to perform endianness
conversion which should be used in favour of manual bit-wrangling.

Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-4-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 11:03:46 +01:00
Marijn Suijten
18a8dd081b backlight: qcom-wled: Override default length with qcom,enabled-strings
[ Upstream commit 2b4b49602f9feca7b7a84eaa33ad9e666c8aa695 ]

The length of qcom,enabled-strings as property array is enough to
determine the number of strings to be enabled, without needing to set
qcom,num-strings to override the default number of strings when less
than the default (which is also the maximum) is provided in DT.

This also introduces an extra warning when qcom,num-strings is set,
denoting that it is not necessary to set both anymore.  It is usually
more concise to set just qcom,num-length when a zero-based, contiguous
range of strings is needed (the majority of the cases), or to only set
qcom,enabled-strings when a specific set of indices is desired.

Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-6-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 11:03:46 +01:00
Marijn Suijten
37b61692f2 backlight: qcom-wled: Fix off-by-one maximum with default num_strings
[ Upstream commit 5ada78b26f935f8751852dffa24f6b545b1d2517 ]

When not specifying num-strings in the DT the default is used, but +1 is
added to it which turns WLED3 into 4 and WLED4/5 into 5 strings instead
of 3 and 4 respectively, causing out-of-bounds reads and register
read/writes.  This +1 exists for a deficiency in the DT parsing code,
and is simply omitted entirely - solving this oob issue - by parsing the
property separately much like qcom,enabled-strings.

This also enables more stringent checks on the maximum value when
qcom,enabled-strings is provided in the DT, by parsing num-strings after
enabled-strings to allow it to check against (and in a subsequent patch
override) the length of enabled-strings: it is invalid to set
num-strings higher than that.
The DT currently utilizes it to get around an incorrect fixed read of
four elements from that array (has been addressed in a prior patch) by
setting a lower num-strings where desired.

Fixes: 93c64f1ea1e8 ("leds: add Qualcomm PM8941 WLED driver")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-By: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-5-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 11:03:46 +01:00
Marijn Suijten
219c7d18be backlight: qcom-wled: Pass number of elements to read to read_u32_array
[ Upstream commit e29e24bdabfeddbf8b1a4ecac1af439a85150438 ]

of_property_read_u32_array takes the number of elements to read as last
argument. This does not always need to be 4 (sizeof(u32)) but should
instead be the size of the array in DT as read just above with
of_property_count_elems_of_size.

To not make such an error go unnoticed again the driver now bails
accordingly when of_property_read_u32_array returns an error.
Surprisingly the indentation of newlined arguments is lining up again
after prepending `rc = `.

Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-3-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 11:03:45 +01:00
Marijn Suijten
f2bc76de28 backlight: qcom-wled: Validate enabled string indices in DT
[ Upstream commit c05b21ebc5bce3ecc78c2c71afd76d92c790a2ac ]

The strings passed in DT may possibly cause out-of-bounds register
accesses and should be validated before use.

Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3")
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-2-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 11:03:45 +01:00
Javier Martinez Canillas
e2ece45f94 video: vga16fb: Only probe for EGA and VGA 16 color graphic cards
commit 0499f419b76f94ede08304aad5851144813ac55c upstream.

The vga16fb framebuffer driver only supports Enhanced Graphics Adapter
(EGA) and Video Graphics Array (VGA) 16 color graphic cards.

But it doesn't check if the adapter is one of those or if a VGA16 mode
is used. This means that the driver will be probed even if a VESA BIOS
Extensions (VBE) or Graphics Output Protocol (GOP) interface is used.

This issue has been present for a long time but it was only exposed by
commit d391c5827107 ("drivers/firmware: move x86 Generic System
Framebuffers support") since the platform device registration to match
the {vesa,efi}fb drivers is done later as a consequence of that change.

All non-x86 architectures though treat orig_video_isVGA as a boolean so
only do the supported video mode check for x86 and not for other arches.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215001
Fixes: d391c5827107 ("drivers/firmware: move x86 Generic System Framebuffers support")
Reported-by: Kris Karas <bugs-a21@moonlit-rail.com>
Cc: <stable@vger.kernel.org> # 5.15.x
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Kris Karas <bugs-a21@moonlit-rail.com>
Acked-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220110095625.278836-3-javierm@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-20 09:13:14 +01:00