linux.git/drivers/video/fbdev/i740fb.c, branch v5.19 Linux kernel source tree video: fbdev: i740fb: Error out if 'pixclock' equals zero 2022-04-11T06:23:50+00:00 Zheyu Ma zheyuma97@gmail.com 2022-04-04T08:47:17+00:00 15cf0b82271b1823fb02ab8c377badba614d95d5 The userspace program could pass any values to the driver through ioctl() interface. If the driver doesn't check the value of 'pixclock', it may cause divide error. Fix this by checking whether 'pixclock' is zero in the function i740fb_check_var(). The following log reveals it: divide error: 0000 [#1] PREEMPT SMP KASAN PTI RIP: 0010:i740fb_decode_var drivers/video/fbdev/i740fb.c:444 [inline] RIP: 0010:i740fb_set_par+0x272f/0x3bb0 drivers/video/fbdev/i740fb.c:739 Call Trace: fb_set_var+0x604/0xeb0 drivers/video/fbdev/core/fbmem.c:1036 do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1112 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1191 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] Signed-off-by: Zheyu Ma <zheyuma97@gmail.com> Signed-off-by: Helge Deller <deller@gmx.de> 
The userspace program could pass any values to the driver through
ioctl() interface. If the driver doesn't check the value of 'pixclock',
it may cause divide error.

Fix this by checking whether 'pixclock' is zero in the function
i740fb_check_var().

The following log reveals it:

divide error: 0000 [#1] PREEMPT SMP KASAN PTI
RIP: 0010:i740fb_decode_var drivers/video/fbdev/i740fb.c:444 [inline]
RIP: 0010:i740fb_set_par+0x272f/0x3bb0 drivers/video/fbdev/i740fb.c:739
Call Trace:
    fb_set_var+0x604/0xeb0 drivers/video/fbdev/core/fbmem.c:1036
    do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1112
    fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1191
    vfs_ioctl fs/ioctl.c:51 [inline]
    __do_sys_ioctl fs/ioctl.c:874 [inline]

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
video: fbdev: i740fb: use memset_io() to clear screen 2022-04-11T06:23:50+00:00 Ondrej Zary linux@zary.sk 2022-04-10T20:28:33+00:00 12acdbd7ca7d8b3ac0f55d8069f52c223d8d23fd sparse complains that using memset() on __iomem pointer is wrong: incorrect type in argument 1 (different address spaces) Use memset_io() to clear screen instead. Tested on real i740 cards. Signed-off-by: Ondrej Zary <linux@zary.sk> Signed-off-by: Helge Deller <deller@gmx.de> 
sparse complains that using memset() on __iomem pointer is wrong:
incorrect type in argument 1 (different address spaces)

Use memset_io() to clear screen instead.

Tested on real i740 cards.

Signed-off-by: Ondrej Zary <linux@zary.sk>
Signed-off-by: Helge Deller <deller@gmx.de>
fbdev: i740fb: use generic power management 2020-09-08T11:33:17+00:00 Vaibhav Gupta vaibhavgupta40@gmail.com 2020-08-19T18:56:51+00:00 805a5c45ff2d51c36e90c675cd751c17632bd502 Drivers should do only device-specific jobs. But in general, drivers using legacy PCI PM framework for .suspend()/.resume() have to manage many PCI PM-related tasks themselves which can be done by PCI Core itself. This brings extra load on the driver and it directly calls PCI helper functions to handle them. Switch to the new generic framework by updating function signatures and define a "struct dev_pm_ops" variable to bind PM callbacks. Also, remove unnecessary calls to the PCI Helper functions along with the legacy .suspend & .resume bindings. The i740fb_suspend() is not designed to function in the case of Freeze. Thus, the code checked for "if (state.event == PM_EVENT_FREEZE....)". This is because, in the legacy framework, this callback was invoked even in the event of Freeze. Hence, added the load of unnecessary function-call. The goal can be achieved by binding the callback with only ".suspend" and ".poweroff" in the "i740fb_pm_ops" const variable. This also avoids the step of checking "if (state.event == PM_EVENT_FREEZE....)" every time the callback is invoked. Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com> Cc: Bjorn Helgaas <helgaas@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Bjorn Helgaas <bjorn@helgaas.com> Cc: Vaibhav Gupta <vaibhav.varodek@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Andres Salomon <dilinger@queued.net> CC: Antonino Daplas <adaplas@gmail.com> Cc: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200819185654.151170-10-vaibhavgupta40@gmail.com 
Drivers should do only device-specific jobs. But in general, drivers using
legacy PCI PM framework for .suspend()/.resume() have to manage many PCI
PM-related tasks themselves which can be done by PCI Core itself. This
brings extra load on the driver and it directly calls PCI helper functions
to handle them.

Switch to the new generic framework by updating function signatures and
define a "struct dev_pm_ops" variable to bind PM callbacks. Also, remove
unnecessary calls to the PCI Helper functions along with the legacy
.suspend & .resume bindings.

The i740fb_suspend() is not designed to function in the case of Freeze.
Thus, the code checked for "if (state.event == PM_EVENT_FREEZE....)". This
is because, in the legacy framework, this callback was invoked even in the
event of Freeze. Hence, added the load of unnecessary function-call.

The goal can be achieved by binding the callback with only ".suspend" and
".poweroff" in the "i740fb_pm_ops" const variable. This also avoids the
step of checking "if (state.event == PM_EVENT_FREEZE....)" every time the
callback is invoked.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Bjorn Helgaas <bjorn@helgaas.com>
Cc: Vaibhav Gupta <vaibhav.varodek@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Andres Salomon <dilinger@queued.net>
CC: Antonino Daplas <adaplas@gmail.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200819185654.151170-10-vaibhavgupta40@gmail.com
fbdev: Use fallthrough pseudo-keyword 2020-08-03T19:38:37+00:00 Gustavo A. R. Silva gustavoars@kernel.org 2020-07-07T21:05:39+00:00 ad04fae0de07580359b7ab3e19a678a775fdf07f Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20200707210539.GA12530@embeddedor 
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200707210539.GA12530@embeddedor
video: constify fb ops across all drivers 2019-12-05T08:57:53+00:00 Jani Nikula jani.nikula@intel.com 2019-12-03T16:38:50+00:00 8a48ac339398f21282985bff16552447d41dcfb2 Now that the fbops member of struct fb_info is const, we can start making the ops const as well. This does not cover all drivers; some actually modify the fbops struct, for example to adjust for different configurations, and others do more involved things that I'd rather not touch in practically obsolete drivers. Mostly this is the low hanging fruit where we can add "const" and be done with it. v3: - un-constify atyfb, mb862xx, nvidia and uvesabf (0day) v2: - fix typo (Christophe de Dinechin) - use "static const" instead of "const static" in mx3fb.c - also constify smscufx.c Cc: linux-fbdev@vger.kernel.org Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/ce67f14435f3af498f2e8bf35ce4be11f7504132.1575390740.git.jani.nikula@intel.com 
Now that the fbops member of struct fb_info is const, we can start
making the ops const as well.

This does not cover all drivers; some actually modify the fbops struct,
for example to adjust for different configurations, and others do more
involved things that I'd rather not touch in practically obsolete
drivers. Mostly this is the low hanging fruit where we can add "const"
and be done with it.

v3:
- un-constify atyfb, mb862xx, nvidia and uvesabf (0day)

v2:
- fix typo (Christophe de Dinechin)
- use "static const" instead of "const static" in mx3fb.c
- also constify smscufx.c

Cc: linux-fbdev@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ce67f14435f3af498f2e8bf35ce4be11f7504132.1575390740.git.jani.nikula@intel.com
video: fbdev: don't print error message on framebuffer_alloc() failure 2019-06-28T10:30:08+00:00 Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com 2019-06-28T10:30:08+00:00 0adcdbcb179624d7b3677264f2cd228e7d89eea9 framebuffer_alloc() can fail only on kzalloc() memory allocation failure and since kzalloc() will print error message in such case we can omit printing extra error message in drivers (which BTW is what the majority of framebuffer_alloc() users is doing already). Cc: "Bruno Prémont" <bonbons@linux-vserver.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> 
framebuffer_alloc() can fail only on kzalloc() memory allocation
failure and since kzalloc() will print error message in such case
we can omit printing extra error message in drivers (which BTW is
what the majority of framebuffer_alloc() users is doing already).

Cc: "Bruno Prémont" <bonbons@linux-vserver.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
treewide: Add SPDX license identifier for more missed files 2019-05-21T08:50:45+00:00 Thomas Gleixner tglx@linutronix.de 2019-05-19T12:08:20+00:00 09c434b8a0047c69e48499de0107de312901e798 Add SPDX license identifiers to all files which: - Have no license information of any form - Have MODULE_LICENCE("GPL*") inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
video: fbdev: mark expected switch fall-throughs 2018-07-24T17:11:28+00:00 Gustavo A. R. Silva gustavo@embeddedor.com 2018-07-24T17:11:28+00:00 12382ad98ca06afb7ce4dce53aebf115b5f6b948 In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> 
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
video: fbdev: constify fb_fix_screeninfo and fb_var_screeninfo structures 2016-09-27T08:16:35+00:00 Julia Lawall Julia.Lawall@lip6.fr 2016-09-11T15:17:20+00:00 ca9384c5911199257cbdf48f1bc3e3986de611a2 These structures are only used to copy into other structures, so declare them as const. The semantic patch that makes this change in the fb_fix_screeninfo case is as follows (http://coccinelle.lip6.fr/). The fb_var_screeninfo case is analogous. // <smpl> @r disable optional_qualifier@ identifier i; position p; @@ static struct fb_fix_screeninfo i@p = { ... }; @ok@ identifier r.i; expression e; position p; @@ e = i@p @bad@ position p != {r.p,ok.p}; identifier r.i; struct fb_fix_screeninfo e; @@ e@i@p @depends on !bad disable optional_qualifier@ identifier r.i; @@ static +const struct fb_fix_screeninfo i = { ... }; // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> 
These structures are only used to copy into other structures, so declare
them as const.

The semantic patch that makes this change in the fb_fix_screeninfo case is
as follows (http://coccinelle.lip6.fr/).  The fb_var_screeninfo case is
analogous.

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct fb_fix_screeninfo i@p = { ... };

@ok@
identifier r.i;
expression e;
position p;
@@
e = i@p

@bad@
position p != {r.p,ok.p};
identifier r.i;
struct fb_fix_screeninfo e;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
 struct fb_fix_screeninfo i = { ... };
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
drivers/video/fbdev/i740fb: remove unused variable 2015-12-15T13:41:21+00:00 Sudip Mukherjee sudipm.mukherjee@gmail.com 2015-10-03T11:16:31+00:00 2168b49a22d8fb2e745a72d5fb47adfbc4a64234 The value of d_best is always 0 and never changes. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> 
The value of d_best is always 0 and never changes.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>