Bug fixes:
- Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds (Albin Babu Varghese)
- Fix logic error in "offb" name match (Finn Thain)
- simplefb: Fix use after free in simplefb_detach_genpds() (Janne Grunau)
- s3fb: Various fixes and powersave improvements (Zsolt Kajtar)
Enhancements & code cleanups:
- Various fixes in the documentation (Bagas Sanjaya)
- Use string choices helpers (Chelsy Ratnawat)
- xenfb: Use vmalloc_array to simplify code (Qianfeng Rong)
- mb862xxfb: Use int type to store negative error codes (Qianfeng Rong)
- Make drivers depend on LCD_CLASS_DEVICE (Thomas Zimmermann)
- radeonfb: Remove stale product link in Kconfig (Sukrut Heroorkar)
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Merge tag 'fbdev-for-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev
Pull fbdev updates from Helge Deller:
"Beside the usual bunch of smaller bug fixes, the majority of changes
were by Zsolt Kajtar to improve the s3fb driver.
Bug fixes:
- Bounds checking to fix vmalloc-out-of-bounds (Albin Babu Varghese)
- Fix logic error in "offb" name match (Finn Thain)
- simplefb: Fix use after free in (Janne Grunau)
- s3fb: Various fixes and powersave improvements (Zsolt Kajtar)
Enhancements & code cleanups:
- Various fixes in the documentation (Bagas Sanjaya)
- Use string choices helpers (Chelsy Ratnawat)
- xenfb: Use vmalloc_array to simplify code (Qianfeng Rong)
- mb862xxfb: use signed type for error codes (Qianfeng Rong)
- Make drivers depend on LCD_CLASS_DEVICE (Thomas Zimmermann)
- radeonfb: Remove stale product link in Kconfig (Sukrut Heroorkar)"
* tag 'fbdev-for-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev:
fbdev: Fix logic error in "offb" name match
fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds
fbdev: Make drivers depend on LCD_CLASS_DEVICE
fbdev: radeonfb: Remove stale product link in Kconfig
Documentation: fb: Retitle driver docs
Documentation: fb: ep93xx: Demote section headings
Documentation: fb: Split toctree
fbdev: simplefb: Fix use after free in simplefb_detach_genpds()
fbdev: s3fb: Revert mclk stop in suspend
fbdev: mb862xxfb: Use int type to store negative error codes
fbdev: Use string choices helpers
fbdev: core: Fix ubsan warning in pixel_to_pat
fbdev: s3fb: Implement 1 and 2 BPP modes, improve 4 BPP
fbdev: s3fb: Implement powersave for S3 FB
fbdev: xenfb: Use vmalloc_array to simplify code
A regression was reported to me recently whereby /dev/fb0 had disappeared
from a PowerBook G3 Series "Wallstreet". The problem shows up when the
"video=ofonly" parameter is passed to the kernel, which is what the
bootloader does when "no video driver" is selected. The cause of the
problem is the "offb" string comparison, which got mangled when it got
refactored. Fix it.
Cc: stable@vger.kernel.org
Fixes: 93604a5ade3a ("fbdev: Handle video= parameter in video/cmdline.c")
Reported-and-tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Add bounds checking to prevent writes past framebuffer boundaries when
rendering text near screen edges. Return early if the Y position is off-screen
and clip image height to screen boundary. Break from the rendering loop if the
X position is off-screen. When clipping image width to fit the screen, update
the character count to match the clipped width to prevent buffer size
mismatches.
Without the character count update, bit_putcs_aligned and bit_putcs_unaligned
receive mismatched parameters where the buffer is allocated for the clipped
width but cnt reflects the original larger count, causing out-of-bounds writes.
Reported-by: syzbot+48b0652a95834717f190@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=48b0652a95834717f190
Suggested-by: Helge Deller <deller@gmx.de>
Tested-by: syzbot+48b0652a95834717f190@syzkaller.appspotmail.com
Signed-off-by: Albin Babu Varghese <albinbabuvarghese20@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
- The 3 patch series "ida: Remove the ida_simple_xxx() API" from
Christophe Jaillet completes the removal of this legacy IDR API.
- The 9 patch series "panic: introduce panic status function family"
from Jinchao Wang provides a number of cleanups to the panic code and
its various helpers, which were rather ad-hoc and scattered all over the
place.
- The 5 patch series "tools/delaytop: implement real-time keyboard
interaction support" from Fan Yu adds a few nice user-facing usability
changes to the delaytop monitoring tool.
- The 3 patch series "efi: Fix EFI boot with kexec handover (KHO)" from
Evangelos Petrongonas fixes a panic which was happening with the
combination of EFI and KHO.
- The 2 patch series "Squashfs: performance improvement and a sanity
check" from Phillip Lougher teaches squashfs's lseek() about
SEEK_DATA/SEEK_HOLE. A mere 150x speedup was measured for a well-chosen
microbenchmark.
- Plus another 50-odd singleton patches all over the place.
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Merge tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
- "ida: Remove the ida_simple_xxx() API" from Christophe Jaillet
completes the removal of this legacy IDR API
- "panic: introduce panic status function family" from Jinchao Wang
provides a number of cleanups to the panic code and its various
helpers, which were rather ad-hoc and scattered all over the place
- "tools/delaytop: implement real-time keyboard interaction support"
from Fan Yu adds a few nice user-facing usability changes to the
delaytop monitoring tool
- "efi: Fix EFI boot with kexec handover (KHO)" from Evangelos
Petrongonas fixes a panic which was happening with the combination of
EFI and KHO
- "Squashfs: performance improvement and a sanity check" from Phillip
Lougher teaches squashfs's lseek() about SEEK_DATA/SEEK_HOLE. A mere
150x speedup was measured for a well-chosen microbenchmark
- plus another 50-odd singleton patches all over the place
* tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (75 commits)
Squashfs: reject negative file sizes in squashfs_read_inode()
kallsyms: use kmalloc_array() instead of kmalloc()
MAINTAINERS: update Sibi Sankar's email address
Squashfs: add SEEK_DATA/SEEK_HOLE support
Squashfs: add additional inode sanity checking
lib/genalloc: fix device leak in of_gen_pool_get()
panic: remove CONFIG_PANIC_ON_OOPS_VALUE
ocfs2: fix double free in user_cluster_connect()
checkpatch: suppress strscpy warnings for userspace tools
cramfs: fix incorrect physical page address calculation
kernel: prevent prctl(PR_SET_PDEATHSIG) from racing with parent process exit
Squashfs: fix uninit-value in squashfs_get_parent
kho: only fill kimage if KHO is finalized
ocfs2: avoid extra calls to strlen() after ocfs2_sprintf_system_inode_name()
kernel/sys.c: fix the racy usage of task_lock(tsk->group_leader) in sys_prlimit64() paths
sched/task.h: fix the wrong comment on task_lock() nesting with tasklist_lock
coccinelle: platform_no_drv_owner: handle also built-in drivers
coccinelle: of_table: handle SPI device ID tables
lib/decompress: use designated initializers for struct compress_format
efi: support booting with kexec handover (KHO)
...
It could be triggered on 32 bit big endian machines at 32 bpp in the
pattern realignment. In this case just return early as the result is
an identity.
Signed-off-by: Zsolt Kajtar <soci@c64.rulez.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Several fbdev drivers select FB_MODE_HELPER in the Kconfig. The
setting controls some helper functions and has no meaning to the
user. Make it an internal option.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20250909132047.152612-3-tzimmermann@suse.de
Commit 1a194e6c8e1e ("fbcon: fix integer overflow in fbcon_do_set_font")
introduced an out-of-bounds access by storing data and allocation sizes
in the same variable. Restore the old size calculation and use the new
variable 'alloc_size' for the allocation.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 1a194e6c8e1e ("fbcon: fix integer overflow in fbcon_do_set_font")
Reported-by: Jani Nikula <jani.nikula@linux.intel.com>
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15020
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6201
Cc: Samasth Norway Ananda <samasth.norway.ananda@oracle.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: George Kennedy <george.kennedy@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: Helge Deller <deller@gmx.de>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Qianqiang Liu <qianqiang.liu@163.com>
Cc: Shixiong Ou <oushixiong@kylinos.cn>
Cc: Kees Cook <kees@kernel.org>
Cc: <stable@vger.kernel.org> # v5.9+
Cc: Zsolt Kajtar <soci@c64.rulez.org>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Qianqiang Liu <qianqiang.liu@163.com>
Link: https://lore.kernel.org/r/20250922134619.257684-1-tzimmermann@suse.de
Fix integer overflow vulnerabilities in fbcon_do_set_font() where font
size calculations could overflow when handling user-controlled font
parameters.
The vulnerabilities occur when:
1. CALC_FONTSZ(h, pitch, charcount) performs h * pith * charcount
multiplication with user-controlled values that can overflow.
2. FONT_EXTRA_WORDS * sizeof(int) + size addition can also overflow
3. This results in smaller allocations than expected, leading to buffer
overflows during font data copying.
Add explicit overflow checking using check_mul_overflow() and
check_add_overflow() kernel helpers to safety validate all size
calculations before allocation.
Signed-off-by: Samasth Norway Ananda <samasth.norway.ananda@oracle.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 39b3cffb8cf3 ("fbcon: prevent user font height or width change from causing potential out-of-bounds access")
Cc: George Kennedy <george.kennedy@oracle.com>
Cc: stable <stable@vger.kernel.org>
Cc: syzbot+38a3699c7eaf165b97a6@syzkaller.appspotmail.com
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: Helge Deller <deller@gmx.de>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Qianqiang Liu <qianqiang.liu@163.com>
Cc: Shixiong Ou <oushixiong@kylinos.cn>
Cc: Kees Cook <kees@kernel.org>
Cc: <stable@vger.kernel.org> # v5.9+
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250912170023.3931881-1-samasth.norway.ananda@oracle.com
Support for console rotation is somewhat bolted onto the helper
fbcon_set_bitops() for unrotated displays.
Update fbcon_set_bitops() with a switch statement that picks the
correct settings helper for the current rotation. For unrotated
consoles, set the bitops for in the new helper fbcon_set_bitops_ur().
Rename the other, existing helpers to match the common naming
scheme.
The old helper fbcon_set_rotate() is no longer used.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/20250909124616.143365-6-tzimmermann@suse.de
Depending on rotation settings, fbcon sets different callback
functions in struct fbcon_par from within fbcon_set_bitops(). Declare
the callback functions in the new type struct fbcon_bitops. Then
only replace the single bitops pointer in struct fbcon_par.
Keeping callbacks in constant instances of struct fbcon_bitops
makes it harder to exploit the callbacks. Also makes the code slightly
easier to maintain.
For tile-based consoles, there's a separate instance of the bitops
structure.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/20250909124616.143365-5-tzimmermann@suse.de
The field struct fbcon_par.rotate_font points to fbcon_rotate_font() if
the console is rotated. Set the callback in the same place as the other
callbacks. Prepares for declaring all fbcon callbacks in a dedicated
struct type.
If not rotated, fbcon_set_bitops() still clears the callback to NULL.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/20250909124616.143365-4-tzimmermann@suse.de
The type struct fbcon_ops contains fbcon state and callbacks. As the
callbacks will be removed from struct fbcon_ops, rename the data type
to struct fbcon_par. Also rename the variables from ops to par.
The _par postfix ("private access registers") is used throughout the
fbdev subsystem for per-driver state. The fbcon pointer within struct
fb_info is also named fbcon_par. Hence, the new naming fits existing
practice.
v2:
- rename struct fbcon_ops to struct fbcon_par
- fix build for CONFIG_FB_TILEBITTING=n (kernel test robot)
- fix indention
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/20250909124616.143365-3-tzimmermann@suse.de
Update the fbcon_skip_panic() function to use the panic_in_progress()
helper.
The previous direct access to panic_cpu is less readable and is being
replaced by a dedicated function that more clearly expresses the intent.
This change is part of a series to refactor the kernel's panic handling
logic for better clarity and robustness.
Link: https://lkml.kernel.org/r/20250825022947.1596226-3-wangjinchao600@gmail.com
Signed-off-by: Jinchao Wang <wangjinchao600@gmail.com>
Acked-by Qianqiang Liu <qianqiang.liu@163.com>
Cc: Anna Schumaker <anna.schumaker@oracle.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Doug Anderson <dianders@chromium.org>
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Kees Cook <kees@kernel.org>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Luo Gengkun <luogengkun@huaweicloud.com>
Cc: Max Kellermann <max.kellermann@ionos.com>
Cc: Nam Cao <namcao@linutronix.de>
Cc: oushixiong <oushixiong@kylinos.cn>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Thomas Zimemrmann <tzimmermann@suse.de>
Cc: Thorsten Blum <thorsten.blum@linux.dev>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Cc: Yunhui Cui <cuiyunhui@bytedance.com>
Cc: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
- Revert a patch which broke VGA console.
- Fix an out-of-bounds access bug which may happen during console
resizing when a console is mapped to a frame buffer.
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Merge tag 'fbdev-for-6.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev
Pull fbdev fixes for 6.17-rc1:
- Revert a patch which broke VGA console
- Fix an out-of-bounds access bug which may happen during console
resizing when a console is mapped to a frame buffer
* tag 'fbdev-for-6.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev:
Revert "vgacon: Add check for vc_origin address range in vgacon_scroll()"
fbdev: Fix vmalloc out-of-bounds write in fast_imageblit
This issue triggers when a userspace program does an ioctl
FBIOPUT_CON2FBMAP by passing console number and frame buffer number.
Ideally this maps console to frame buffer and updates the screen if
console is visible.
As part of mapping it has to do resize of console according to frame
buffer info. if this resize fails and returns from vc_do_resize() and
continues further. At this point console and new frame buffer are mapped
and sets display vars. Despite failure still it continue to proceed
updating the screen at later stages where vc_data is related to previous
frame buffer and frame buffer info and display vars are mapped to new
frame buffer and eventully leading to out-of-bounds write in
fast_imageblit(). This bheviour is excepted only when fg_console is
equal to requested console which is a visible console and updates screen
with invalid struct references in fbcon_putcs().
Reported-and-tested-by: syzbot+c4b7aa0513823e2ea880@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c4b7aa0513823e2ea880
Signed-off-by: Sravan Kumar Gundu <sravankumarlpu@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Use 'bool' type where it makes more sense than 'int'.
v2: Rebase due to corrected 'fbcon_cursor_blink' initial value
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Make the code more legible by adding get_{fg,bg}_color()
which hide the obscure 'is_fg' parameter of get_color()
from the caller.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Helge Deller <deller@gmx.de>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Invert fbcon_is_inactive() into fbcon_is_active(). Much easier
on the poor brain when you don't have to do dobule negations
all over the place.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Helge Deller <deller@gmx.de>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Invert fbcon_cursor_noblink into fbcon_cursor_blink so that:
- it matches the sysfs attribute exactly
- avoids having to do these NOT operations all over the place
- use bool instead of int
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Seems like someone hit 'c' when they meant to hit 'd'.
Signed-off-by: Daniel Palmer <daniel.palmer@sony.com>
Signed-off-by: Helge Deller <deller@gmx.de>
This patch addresses various coding style issues in `svgalib.c` to improve
readability and better align the code with the Linux kernel's formatting
standards.
The changes primarily consist of:
- Adjusting whitespace around operators and after keywords.
- Standardizing brace placement for control flow statements.
- Removing unnecessary braces on single-statement if/else blocks.
- Deleting extraneous blank lines throughout the file.
These changes are purely stylistic and introduce no functional modifications.
Signed-off-by: Darshan R. <rathod.darshan.0896@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
The current implementation may lead to buffer overflow when:
1. Unregistration creates NULL gaps in registered_fb[]
2. All array slots become occupied despite num_registered_fb < FB_MAX
3. The registration loop exceeds array bounds
Add boundary check to prevent registered_fb[FB_MAX] access.
Signed-off-by: Yongzhen Zhang <zhangyongzhen@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
The variable was renamed to fbcon_registered_fb, but this comment was
not updated along with the change. Correct it to avoid confusion.
Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Fixes: efc3acbc105a ("fbcon: Maintain a private array of fb_info")
[sima: Add Fixes: line.]
Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20250709103438.572309-1-oushixiong1025@163.com
DRM drivers such as efidrm and vesadrm can export firmware EDID
data to userspace. Make the related option CONFIG_FIRMWARE_EDID
available without CONFIG_FB. Make it depend on X86, which is
currently the only architecture providing EDID information.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Link: https://lore.kernel.org/r/20250602075537.137759-2-tzimmermann@suse.de
Fix the compile-time warnings
drivers/video/fbdev/core/cfbcopyarea.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/cfbfillrect.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/cfbimgblt.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/fb_ddc.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/fb_defio.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/fb_io_fops.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/fb_sys_fops.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/fbcmap.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/fbcon.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/fbmon.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/modedb.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/svgalib.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/syscopyarea.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/sysfillrect.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/core/sysimgblt.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/macmodes.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/sbuslib.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
drivers/video/fbdev/wmt_ge_rops.c: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Fixes: a934a57a42f6 ("scripts/misc-check: check missing #include <linux/export.h> when W=1")
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250612081738.197826-3-tzimmermann@suse.de
* Framebuffer Subsystem (fbdev):
* The display's blanking status is now tracked in `struct fb_info`
* `framebuffer_alloc()` initializes the blank state to `FB_BLANK_UNBLANK`
* `register_framebuffer()` sets the state to `FB_BLANK_POWERDOWN` if an `fb_blank`
callback exists, ensuring `FB_EVENT_BLANK` listeners correctly see the display
being turned on during the first modeset
* The `FB_EVENT_BLANK` event data now includes both the new and the old blank states
* Qualcomm WLED Backlight:
* Added a NULL check after `devm_kasprintf()` in `wled_configure()` to prevent a
potential NULL pointer dereference if memory allocation fails
* Framebuffer Subsystem (fbdev):
* `fb_blank()` has been reworked to return early on errors, without functional
changes, in preparation for further state tracking improvements
* Fbdev now calls dedicated functions in the backlight subsystems to notify them
of blank state changes, instead of relying on fbdev event notifiers
* For LCDs, fbdev also calls a dedicated function to notify of mode changes
* Backlight Subsystem:
* Implemented fbdev blank state tracking using the (newly enhanced) blank state
information provided directly by `FB_EVENT_BLANK`
* Removed internal blank state tracking fields (`fb_bl_on`) from
`struct backlight_device`
* Moved the handling of blank-state updates into a separate internal helper
function, `backlight_notify_blank()`
* Removed support for fbdev events and replaced it with a dedicated function call
interface (`backlight_notify_blank()` and `backlight_notify_blank_all()`) for
display drivers to update backlight status
* LCD Subsystem:
* Moved the handling of display updates (blank events and mode changes) from
fbdev event notifiers to separate internal helper functions (`lcd_notify_blank`,
`lcd_notify_mode_change`)
* Removed support for fbdev events and replaced it with dedicated function call
interfaces (`lcd_notify_blank_all()`, `lcd_notify_mode_change_all()`)
* The LCD subsystem now maintains its own internal list of LCD devices instead of
relying on fbdev notifiers
* LED Backlight Trigger:
* Moved the handling of blank-state updates into a separate internal helper,
`ledtrig_backlight_notify_blank()`
* Removed support for fbdev events and replaced it with a dedicated function call,
`ledtrig_backlight_blank()`, for fbdev to notify trigger of blank state changes
* The LED backlight trigger now maintains its own internal list of triggers
instead of relying on fbdev notifiers
* Framebuffer Subsystem (fbdev):
* Removed the definitions for the unused fbdev event constants
`FB_EVENT_MODE_CHANGE` and `FB_EVENT_BLANK` from the header file
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Merge tag 'backlight-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
"Framebuffer Subsystem (fbdev):
- The display's blanking status is now tracked in 'struct fb_info'
- 'framebuffer_alloc()' initializes the blank state to FB_BLANK_UNBLANK
- 'register_framebuffer()' sets the state to 'FB_BLANK_POWERDOWN' if
an 'fb_blank' callback exists, ensuring 'FB_EVENT_BLANK' listeners
correctly see the display being turned on during the first modeset
- The 'FB_EVENT_BLANK' event data now includes both the new and the
old blank states
- 'fb_blank()' has been reworked to return early on errors, without
functional changes, in preparation for further state tracking
improvements
- Fbdev now calls dedicated functions in the backlight subsystems to
notify them of blank state changes, instead of relying on fbdev
event notifiers
- For LCDs, fbdev also calls a dedicated function to notify of mode
changes
- Removed the definitions for the unused fbdev event constants
'FB_EVENT_MODE_CHANGE' and 'FB_EVENT_BLANK' from the header file
Backlight Subsystem:
- Implemented fbdev blank state tracking using the (newly enhanced)
blank state information provided directly by 'FB_EVENT_BLANK'
- Removed internal blank state tracking fields ('fb_bl_on') from
'struct backlight_device'
- Moved the handling of blank-state updates into a separate internal
helper function, 'backlight_notify_blank()'
- Removed support for fbdev events and replaced it with a dedicated
function call interface ('backlight_notify_blank()' and
'backlight_notify_blank_all()') for display drivers to update
backlight status
LCD Subsystem:
- Moved the handling of display updates (blank events and mode
changes) from fbdev event notifiers to separate internal helper
functions ('lcd_notify_blank',
'lcd_notify_mode_change')
- Removed support for fbdev events and replaced it with dedicated
function call interfaces ('lcd_notify_blank_all()',
'lcd_notify_mode_change_all()')
- The LCD subsystem now maintains its own internal list of LCD
devices instead of relying on fbdev notifiers
LED Backlight Trigger:
- Moved the handling of blank-state updates into a separate internal
helper, 'ledtrig_backlight_notify_blank()'
- Removed support for fbdev events and replaced it with a dedicated
function call, 'ledtrig_backlight_blank()', for fbdev to notify
trigger of blank state changes
- The LED backlight trigger now maintains its own internal list of
triggers instead of relying on fbdev notifiers
Qualcomm WLED Backlight:
- Added a NULL check after 'devm_kasprintf()' in 'wled_configure()'
to prevent a potential NULL pointer dereference if memory
allocation fails"
* tag 'backlight-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
backlight: pm8941: Add NULL check in wled_configure()
fbdev: Remove constants of unused events
leds: backlight trigger: Replace fb events with a dedicated function call
leds: backlight trigger: Move blank-state handling into helper
backlight: lcd: Replace fb events with a dedicated function call
backlight: lcd: Move event handling into helpers
backlight: Replace fb events with a dedicated function call
backlight: Move blank-state handling into helper
backlight: Implement fbdev tracking with blank state from event
fbdev: Send old blank state in FB_EVENT_BLANK
fbdev: Track display blanking state
fbdev: Rework fb_blank()
If fb_add_videomode() in fb_set_var() fails to allocate memory for
fb_videomode, later it may lead to a null-ptr dereference in
fb_videomode_to_var(), as the fb_info is registered while not having the
mode in modelist that is expected to be there, i.e. the one that is
described in fb_info->var.
================================================================
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901
Call Trace:
display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929
fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071
resize_screen drivers/tty/vt/vt.c:1176 [inline]
vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263
fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720
fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776
do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128
fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739
do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x67/0xd1
================================================================
The reason is that fb_info->var is being modified in fb_set_var(), and
then fb_videomode_to_var() is called. If it fails to add the mode to
fb_info->modelist, fb_set_var() returns error, but does not restore the
old value of fb_info->var. Restore fb_info->var on failure the same way
it is done earlier in the function.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
If fb_add_videomode() in do_register_framebuffer() fails to allocate
memory for fb_videomode, it will later lead to a null-ptr dereference in
fb_videomode_to_var(), as the fb_info is registered while not having the
mode in modelist that is expected to be there, i.e. the one that is
described in fb_info->var.
================================================================
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901
Call Trace:
display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929
fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071
resize_screen drivers/tty/vt/vt.c:1176 [inline]
vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263
fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720
fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776
do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128
fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739
do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x67/0xd1
================================================================
Even though fbcon_init() checks beforehand if fb_match_mode() in
var_to_display() fails, it can not prevent the panic because fbcon_init()
does not return error code. Considering this and the comment in the code
about fb_match_mode() returning NULL - "This should not happen" - it is
better to prevent registering the fb_info if its mode was not set
successfully. Also move fb_add_videomode() closer to the beginning of
do_register_framebuffer() to avoid having to do the cleanup on fail.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
In fb_find_mode_cvt(), iff mode->refresh somehow happens to be 0x80000000,
cvt.f_refresh will become 0 when multiplying it by 2 due to overflow. It's
then passed to fb_cvt_hperiod(), where it's used as a divider -- division
by 0 will result in kernel oops. Add a sanity check for cvt.f_refresh to
avoid such overflow...
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
Fixes: 96fe6a2109db ("[PATCH] fbdev: Add VESA Coordinated Video Timings (CVT) support")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
It looks like attempting to write to the "store_modes" sysfs node will
run afoul of unregistered consoles:
UBSAN: array-index-out-of-bounds in drivers/video/fbdev/core/fbcon.c:122:28
index -1 is out of range for type 'fb_info *[32]'
...
fbcon_info_from_console+0x192/0x1a0 drivers/video/fbdev/core/fbcon.c:122
fbcon_new_modelist+0xbf/0x2d0 drivers/video/fbdev/core/fbcon.c:3048
fb_new_modelist+0x328/0x440 drivers/video/fbdev/core/fbmem.c:673
store_modes+0x1c9/0x3e0 drivers/video/fbdev/core/fbsysfs.c:113
dev_attr_store+0x55/0x80 drivers/base/core.c:2439
static struct fb_info *fbcon_registered_fb[FB_MAX];
...
static signed char con2fb_map[MAX_NR_CONSOLES];
...
static struct fb_info *fbcon_info_from_console(int console)
...
return fbcon_registered_fb[con2fb_map[console]];
If con2fb_map contains a -1 things go wrong here. Instead, return NULL,
as callers of fbcon_info_from_console() are trying to compare against
existing "info" pointers, so error handling should kick in correctly.
Reported-by: syzbot+a7d4444e7b6e743572f7@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/679d0a8f.050a0220.163cdc.000c.GAE@google.com/
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Remove support for fb events from the led backlight trigger. Provide
the helper ledtrig_backlight_blank() instead. Call it from fbdev to
inform the trigger of changes to a display's blank state.
Fbdev maintains a list of all installed notifiers. Instead of the fbdev
notifiers, maintain an internal list of led backlight triggers.
v3:
- export ledtrig_backlight_blank()
v2:
- maintain global list of led backlight triggers (Lee)
- avoid IS_REACHABLE() in source file (Lee)
- notify on changes to blank state instead of display state
- use lock guards
- initialize led list and list mutex
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Simona Vetter <simona.vetter@ffwll.ch>
Link: https://lore.kernel.org/r/20250321095517.313713-11-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>
Remove support for fb events from the lcd subsystem. Provide the
helper lcd_notify_blank_all() instead. In fbdev, call
lcd_notify_blank_all() to inform the lcd subsystem of changes
to a display's blank state.
Fbdev maintains a list of all installed notifiers. Instead of fbdev
notifiers, maintain an internal list of lcd devices.
v3:
- export lcd_notify_mode_change_all() (kernel test robot)
v2:
- maintain global list of lcd devices
- avoid IS_REACHABLE() in source file
- use lock guards
- initialize lcd list and list mutex
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Simona Vetter <simona.vetter@ffwll.ch>
Reviewed-by: "Daniel Thompson (RISCstar)" <danielt@kernel.org>
Link: https://lore.kernel.org/r/20250321095517.313713-9-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>
Remove support for fb events from backlight subsystem. Provide the
helper backlight_notify_blank_all() instead. Also export the existing
helper backlight_notify_blank() to update a single backlight device.
In fbdev, call either helper to inform the backlight subsystem of
changes to a display's blank state. If the framebuffer device has a
specific backlight, only update this one; otherwise update all.
v4:
- protect blacklight declarations with IS_REACHABLE() (kernel test robot)
v3:
- declare empty fb_bl_notify_blank() as static inline (kernel test robot)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Simona Vetter <simona.vetter@ffwll.ch>
Reviewed-by: "Daniel Thompson (RISCstar)" <danielt@kernel.org>
Link: https://lore.kernel.org/r/20250321095517.313713-7-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>
The event FB_EVENT_BLANK sends the new blank state in the event's
data field. Also send the old state. It's an additional field in the
data array; existing receivers won't notice the difference.
The backlight subsystem currently tracks blank state per display per
backlight. That is not optimal as it ties backlight code to fbdev. A
subsystem should not track internal state of another subsystem. With
both, new and old, blank state in FB_EVENT_BLANK, the backlight code
will not require its own state tracker any longer.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Simona Vetter <simona.vetter@ffwll.ch>
Link: https://lore.kernel.org/r/20250321095517.313713-4-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>
Store the display's blank status in struct fb_info.blank and track
it in fb_blank(). As an extra, the status is now available from the
sysfs blank attribute.
Support for blanking is optional. Therefore framebuffer_alloc()
initializes the state to FB_BLANK_UNBLANK (i.e., the display is
on). If the fb_blank callback has been set, register_framebuffer()
sets the state to FB_BLANK_POWERDOWN. On the first modeset, the
call to fb_blank() will update it to _UNBLANK. This is important,
as listeners to FB_EVENT_BLANK will now see the display being
switched on.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Simona Vetter <simona.vetter@ffwll.ch>
Link: https://lore.kernel.org/r/20250321095517.313713-3-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>
Reimplement fb_blank() to return early on errors. No functional
changes. Prepares the helper for tracking the blanking state in
struct fb_info.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Simona Vetter <simona.vetter@ffwll.ch>
Link: https://lore.kernel.org/r/20250321095517.313713-2-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>
Uros Bizjak uses x86 named address space qualifiers to provide
compile-time checking of percpu area accesses.
This has caused a small amount of fallout - two or three issues were
reported. In all cases the calling code was founf to be incorrect.
- The 4 patch series "Some cleanup for memcg" from Chen Ridong
implements some relatively monir cleanups for the memcontrol code.
- The 17 patch series "mm: fixes for device-exclusive entries (hmm)"
from David Hildenbrand fixes a boatload of issues which David found then
using device-exclusive PTE entries when THP is enabled. More work is
needed, but this makes thins better - our own HMM selftests now succeed.
- The 2 patch series "mm: zswap: remove z3fold and zbud" from Yosry
Ahmed remove the z3fold and zbud implementations. They have been
deprecated for half a year and nobody has complained.
- The 5 patch series "mm: further simplify VMA merge operation" from
Lorenzo Stoakes implements numerous simplifications in this area. No
runtime effects are anticipated.
- The 4 patch series "mm/madvise: remove redundant mmap_lock operations
from process_madvise()" from SeongJae Park rationalizes the locking in
the madvise() implementation. Performance gains of 20-25% were observed
in one MADV_DONTNEED microbenchmark.
- The 12 patch series "Tiny cleanup and improvements about SWAP code"
from Baoquan He contains a number of touchups to issues which Baoquan
noticed when working on the swap code.
- The 2 patch series "mm: kmemleak: Usability improvements" from Catalin
Marinas implements a couple of improvements to the kmemleak user-visible
output.
- The 2 patch series "mm/damon/paddr: fix large folios access and
schemes handling" from Usama Arif provides a couple of fixes for DAMON's
handling of large folios.
- The 3 patch series "mm/damon/core: fix wrong and/or useless
damos_walk() behaviors" from SeongJae Park fixes a few issues with the
accuracy of kdamond's walking of DAMON regions.
- The 3 patch series "expose mapping wrprotect, fix fb_defio use" from
Lorenzo Stoakes changes the interaction between framebuffer deferred-io
and core MM. No functional changes are anticipated - this is
preparatory work for the future removal of page structure fields.
- The 4 patch series "mm/damon: add support for hugepage_size DAMOS
filter" from Usama Arif adds a DAMOS filter which permits the filtering
by huge page sizes.
- The 4 patch series "mm: permit guard regions for file-backed/shmem
mappings" from Lorenzo Stoakes extends the guard region feature from its
present "anon mappings only" state. The feature now covers shmem and
file-backed mappings.
- The 4 patch series "mm: batched unmap lazyfree large folios during
reclamation" from Barry Song cleans up and speeds up the unmapping for
pte-mapped large folios.
- The 18 patch series "reimplement per-vma lock as a refcount" from
Suren Baghdasaryan puts the vm_lock back into the vma. Our reasons for
pulling it out were largely bogus and that change made the code more
messy. This patchset provides small (0-10%) improvements on one
microbenchmark.
- The 5 patch series "Docs/mm/damon: misc DAMOS filters documentation
fixes and improves" from SeongJae Park does some maintenance work on the
DAMON docs.
- The 27 patch series "hugetlb/CMA improvements for large systems" from
Frank van der Linden addresses a pile of issues which have been observed
when using CMA on large machines.
- The 2 patch series "mm/damon: introduce DAMOS filter type for unmapped
pages" from SeongJae Park enables users of DMAON/DAMOS to filter my the
page's mapped/unmapped status.
- The 19 patch series "zsmalloc/zram: there be preemption" from Sergey
Senozhatsky teaches zram to run its compression and decompression
operations preemptibly.
- The 12 patch series "selftests/mm: Some cleanups from trying to run
them" from Brendan Jackman fixes a pile of unrelated issues which
Brendan encountered while runnimg our selftests.
- The 2 patch series "fs/proc/task_mmu: add guard region bit to pagemap"
from Lorenzo Stoakes permits userspace to use /proc/pid/pagemap to
determine whether a particular page is a guard page.
- The 7 patch series "mm, swap: remove swap slot cache" from Kairui Song
removes the swap slot cache from the allocation path - it simply wasn't
being effective.
- The 5 patch series "mm: cleanups for device-exclusive entries (hmm)"
from David Hildenbrand implements a number of unrelated cleanups in this
code.
- The 5 patch series "mm: Rework generic PTDUMP configs" from Anshuman
Khandual implements a number of preparatoty cleanups to the
GENERIC_PTDUMP Kconfig logic.
- The 8 patch series "mm/damon: auto-tune aggregation interval" from
SeongJae Park implements a feedback-driven automatic tuning feature for
DAMON's aggregation interval tuning.
- The 5 patch series "Fix lazy mmu mode" from Ryan Roberts fixes some
issues in powerpc, sparc and x86 lazy MMU implementations. Ryan did
this in preparation for implementing lazy mmu mode for arm64 to optimize
vmalloc.
- The 2 patch series "mm/page_alloc: Some clarifications for migratetype
fallback" from Brendan Jackman reworks some commentary to make the code
easier to follow.
- The 3 patch series "page_counter cleanup and size reduction" from
Shakeel Butt cleans up the page_counter code and fixes a size increase
which we accidentally added late last year.
- The 3 patch series "Add a command line option that enables control of
how many threads should be used to allocate huge pages" from Thomas
Prescher does that. It allows the careful operator to significantly
reduce boot time by tuning the parallalization of huge page
initialization.
- The 3 patch series "Fix calculations in trace_balance_dirty_pages()
for cgwb" from Tang Yizhou fixes the tracing output from the dirty page
balancing code.
- The 9 patch series "mm/damon: make allow filters after reject filters
useful and intuitive" from SeongJae Park improves the handling of allow
and reject filters. Behaviour is made more consistent and the
documention is updated accordingly.
- The 5 patch series "Switch zswap to object read/write APIs" from Yosry
Ahmed updates zswap to the new object read/write APIs and thus permits
the removal of some legacy code from zpool and zsmalloc.
- The 6 patch series "Some trivial cleanups for shmem" from Baolin Wang
does as it claims.
- The 20 patch series "fs/dax: Fix ZONE_DEVICE page reference counts"
from Alistair Popple regularizes the weird ZONE_DEVICE page refcount
handling in DAX, permittig the removal of a number of special-case
checks.
- The 4 patch series "refactor mremap and fix bug" from Lorenzo Stoakes
is a preparatoty refactoring and cleanup of the mremap() code.
- The 20 patch series "mm: MM owner tracking for large folios (!hugetlb)
+ CONFIG_NO_PAGE_MAPCOUNT" from David Hildenbrand reworks the manner in
which we determine whether a large folio is known to be mapped
exclusively into a single MM.
- The 8 patch series "mm/damon: add sysfs dirs for managing DAMOS
filters based on handling layers" from SeongJae Park adds a couple of
new sysfs directories to ease the management of DAMON/DAMOS filters.
- The 13 patch series "arch, mm: reduce code duplication in mem_init()"
from Mike Rapoport consolidates many per-arch implementations of
mem_init() into code generic code, where that is practical.
- The 13 patch series "mm/damon/sysfs: commit parameters online via
damon_call()" from SeongJae Park continues the cleaning up of sysfs
access to DAMON internal data.
- The 3 patch series "mm: page_ext: Introduce new iteration API" from
Luiz Capitulino reworks the page_ext initialization to fix a boot-time
crash which was observed with an unusual combination of compile and
cmdline options.
- The 8 patch series "Buddy allocator like (or non-uniform) folio split"
from Zi Yan reworks the code to split a folio into smaller folios. The
main benefit is lessened memory consumption: fewer post-split folios are
generated.
- The 2 patch series "Minimize xa_node allocation during xarry split"
from Zi Yan reduces the number of xarray xa_nodes which are generated
during an xarray split.
- The 2 patch series "drivers/base/memory: Two cleanups" from Gavin Shan
performs some maintenance work on the drivers/base/memory code.
- The 3 patch series "Add tracepoints for lowmem reserves, watermarks
and totalreserve_pages" from Martin Liu adds some more tracepoints to
the page allocator code.
- The 4 patch series "mm/madvise: cleanup requests validations and
classifications" from SeongJae Park cleans up some warts which SeongJae
observed during his earlier madvise work.
- The 3 patch series "mm/hwpoison: Fix regressions in memory failure
handling" from Shuai Xue addresses two quite serious regressions which
Shuai has observed in the memory-failure implementation.
- The 5 patch series "mm: reliable huge page allocator" from Johannes
Weiner makes huge page allocations cheaper and more reliable by reducing
fragmentation.
- The 5 patch series "Minor memcg cleanups & prep for memdescs" from
Matthew Wilcox is preparatory work for the future implementation of
memdescs.
- The 4 patch series "track memory used by balloon drivers" from Nico
Pache introduces a way to track memory used by our various balloon
drivers.
- The 2 patch series "mm/damon: introduce DAMOS filter type for active
pages" from Nhat Pham permits users to filter for active/inactive pages,
separately for file and anon pages.
- The 2 patch series "Adding Proactive Memory Reclaim Statistics" from
Hao Jia separates the proactive reclaim statistics from the direct
reclaim statistics.
- The 2 patch series "mm/vmscan: don't try to reclaim hwpoison folio"
from Jinjiang Tu fixes our handling of hwpoisoned pages within the
reclaim code.
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Merge tag 'mm-stable-2025-03-30-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- The series "Enable strict percpu address space checks" from Uros
Bizjak uses x86 named address space qualifiers to provide
compile-time checking of percpu area accesses.
This has caused a small amount of fallout - two or three issues were
reported. In all cases the calling code was found to be incorrect.
- The series "Some cleanup for memcg" from Chen Ridong implements some
relatively monir cleanups for the memcontrol code.
- The series "mm: fixes for device-exclusive entries (hmm)" from David
Hildenbrand fixes a boatload of issues which David found then using
device-exclusive PTE entries when THP is enabled. More work is
needed, but this makes thins better - our own HMM selftests now
succeed.
- The series "mm: zswap: remove z3fold and zbud" from Yosry Ahmed
remove the z3fold and zbud implementations. They have been deprecated
for half a year and nobody has complained.
- The series "mm: further simplify VMA merge operation" from Lorenzo
Stoakes implements numerous simplifications in this area. No runtime
effects are anticipated.
- The series "mm/madvise: remove redundant mmap_lock operations from
process_madvise()" from SeongJae Park rationalizes the locking in the
madvise() implementation. Performance gains of 20-25% were observed
in one MADV_DONTNEED microbenchmark.
- The series "Tiny cleanup and improvements about SWAP code" from
Baoquan He contains a number of touchups to issues which Baoquan
noticed when working on the swap code.
- The series "mm: kmemleak: Usability improvements" from Catalin
Marinas implements a couple of improvements to the kmemleak
user-visible output.
- The series "mm/damon/paddr: fix large folios access and schemes
handling" from Usama Arif provides a couple of fixes for DAMON's
handling of large folios.
- The series "mm/damon/core: fix wrong and/or useless damos_walk()
behaviors" from SeongJae Park fixes a few issues with the accuracy of
kdamond's walking of DAMON regions.
- The series "expose mapping wrprotect, fix fb_defio use" from Lorenzo
Stoakes changes the interaction between framebuffer deferred-io and
core MM. No functional changes are anticipated - this is preparatory
work for the future removal of page structure fields.
- The series "mm/damon: add support for hugepage_size DAMOS filter"
from Usama Arif adds a DAMOS filter which permits the filtering by
huge page sizes.
- The series "mm: permit guard regions for file-backed/shmem mappings"
from Lorenzo Stoakes extends the guard region feature from its
present "anon mappings only" state. The feature now covers shmem and
file-backed mappings.
- The series "mm: batched unmap lazyfree large folios during
reclamation" from Barry Song cleans up and speeds up the unmapping
for pte-mapped large folios.
- The series "reimplement per-vma lock as a refcount" from Suren
Baghdasaryan puts the vm_lock back into the vma. Our reasons for
pulling it out were largely bogus and that change made the code more
messy. This patchset provides small (0-10%) improvements on one
microbenchmark.
- The series "Docs/mm/damon: misc DAMOS filters documentation fixes and
improves" from SeongJae Park does some maintenance work on the DAMON
docs.
- The series "hugetlb/CMA improvements for large systems" from Frank
van der Linden addresses a pile of issues which have been observed
when using CMA on large machines.
- The series "mm/damon: introduce DAMOS filter type for unmapped pages"
from SeongJae Park enables users of DMAON/DAMOS to filter my the
page's mapped/unmapped status.
- The series "zsmalloc/zram: there be preemption" from Sergey
Senozhatsky teaches zram to run its compression and decompression
operations preemptibly.
- The series "selftests/mm: Some cleanups from trying to run them" from
Brendan Jackman fixes a pile of unrelated issues which Brendan
encountered while runnimg our selftests.
- The series "fs/proc/task_mmu: add guard region bit to pagemap" from
Lorenzo Stoakes permits userspace to use /proc/pid/pagemap to
determine whether a particular page is a guard page.
- The series "mm, swap: remove swap slot cache" from Kairui Song
removes the swap slot cache from the allocation path - it simply
wasn't being effective.
- The series "mm: cleanups for device-exclusive entries (hmm)" from
David Hildenbrand implements a number of unrelated cleanups in this
code.
- The series "mm: Rework generic PTDUMP configs" from Anshuman Khandual
implements a number of preparatoty cleanups to the GENERIC_PTDUMP
Kconfig logic.
- The series "mm/damon: auto-tune aggregation interval" from SeongJae
Park implements a feedback-driven automatic tuning feature for
DAMON's aggregation interval tuning.
- The series "Fix lazy mmu mode" from Ryan Roberts fixes some issues in
powerpc, sparc and x86 lazy MMU implementations. Ryan did this in
preparation for implementing lazy mmu mode for arm64 to optimize
vmalloc.
- The series "mm/page_alloc: Some clarifications for migratetype
fallback" from Brendan Jackman reworks some commentary to make the
code easier to follow.
- The series "page_counter cleanup and size reduction" from Shakeel
Butt cleans up the page_counter code and fixes a size increase which
we accidentally added late last year.
- The series "Add a command line option that enables control of how
many threads should be used to allocate huge pages" from Thomas
Prescher does that. It allows the careful operator to significantly
reduce boot time by tuning the parallalization of huge page
initialization.
- The series "Fix calculations in trace_balance_dirty_pages() for cgwb"
from Tang Yizhou fixes the tracing output from the dirty page
balancing code.
- The series "mm/damon: make allow filters after reject filters useful
and intuitive" from SeongJae Park improves the handling of allow and
reject filters. Behaviour is made more consistent and the documention
is updated accordingly.
- The series "Switch zswap to object read/write APIs" from Yosry Ahmed
updates zswap to the new object read/write APIs and thus permits the
removal of some legacy code from zpool and zsmalloc.
- The series "Some trivial cleanups for shmem" from Baolin Wang does as
it claims.
- The series "fs/dax: Fix ZONE_DEVICE page reference counts" from
Alistair Popple regularizes the weird ZONE_DEVICE page refcount
handling in DAX, permittig the removal of a number of special-case
checks.
- The series "refactor mremap and fix bug" from Lorenzo Stoakes is a
preparatoty refactoring and cleanup of the mremap() code.
- The series "mm: MM owner tracking for large folios (!hugetlb) +
CONFIG_NO_PAGE_MAPCOUNT" from David Hildenbrand reworks the manner in
which we determine whether a large folio is known to be mapped
exclusively into a single MM.
- The series "mm/damon: add sysfs dirs for managing DAMOS filters based
on handling layers" from SeongJae Park adds a couple of new sysfs
directories to ease the management of DAMON/DAMOS filters.
- The series "arch, mm: reduce code duplication in mem_init()" from
Mike Rapoport consolidates many per-arch implementations of
mem_init() into code generic code, where that is practical.
- The series "mm/damon/sysfs: commit parameters online via
damon_call()" from SeongJae Park continues the cleaning up of sysfs
access to DAMON internal data.
- The series "mm: page_ext: Introduce new iteration API" from Luiz
Capitulino reworks the page_ext initialization to fix a boot-time
crash which was observed with an unusual combination of compile and
cmdline options.
- The series "Buddy allocator like (or non-uniform) folio split" from
Zi Yan reworks the code to split a folio into smaller folios. The
main benefit is lessened memory consumption: fewer post-split folios
are generated.
- The series "Minimize xa_node allocation during xarry split" from Zi
Yan reduces the number of xarray xa_nodes which are generated during
an xarray split.
- The series "drivers/base/memory: Two cleanups" from Gavin Shan
performs some maintenance work on the drivers/base/memory code.
- The series "Add tracepoints for lowmem reserves, watermarks and
totalreserve_pages" from Martin Liu adds some more tracepoints to the
page allocator code.
- The series "mm/madvise: cleanup requests validations and
classifications" from SeongJae Park cleans up some warts which
SeongJae observed during his earlier madvise work.
- The series "mm/hwpoison: Fix regressions in memory failure handling"
from Shuai Xue addresses two quite serious regressions which Shuai
has observed in the memory-failure implementation.
- The series "mm: reliable huge page allocator" from Johannes Weiner
makes huge page allocations cheaper and more reliable by reducing
fragmentation.
- The series "Minor memcg cleanups & prep for memdescs" from Matthew
Wilcox is preparatory work for the future implementation of memdescs.
- The series "track memory used by balloon drivers" from Nico Pache
introduces a way to track memory used by our various balloon drivers.
- The series "mm/damon: introduce DAMOS filter type for active pages"
from Nhat Pham permits users to filter for active/inactive pages,
separately for file and anon pages.
- The series "Adding Proactive Memory Reclaim Statistics" from Hao Jia
separates the proactive reclaim statistics from the direct reclaim
statistics.
- The series "mm/vmscan: don't try to reclaim hwpoison folio" from
Jinjiang Tu fixes our handling of hwpoisoned pages within the reclaim
code.
* tag 'mm-stable-2025-03-30-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (431 commits)
mm/page_alloc: remove unnecessary __maybe_unused in order_to_pindex()
x86/mm: restore early initialization of high_memory for 32-bits
mm/vmscan: don't try to reclaim hwpoison folio
mm/hwpoison: introduce folio_contain_hwpoisoned_page() helper
cgroup: docs: add pswpin and pswpout items in cgroup v2 doc
mm: vmscan: split proactive reclaim statistics from direct reclaim statistics
selftests/mm: speed up split_huge_page_test
selftests/mm: uffd-unit-tests support for hugepages > 2M
docs/mm/damon/design: document active DAMOS filter type
mm/damon: implement a new DAMOS filter type for active pages
fs/dax: don't disassociate zero page entries
MM documentation: add "Unaccepted" meminfo entry
selftests/mm: add commentary about 9pfs bugs
fork: use __vmalloc_node() for stack allocation
docs/mm: Physical Memory: Populate the "Zones" section
xen: balloon: update the NR_BALLOON_PAGES state
hv_balloon: update the NR_BALLOON_PAGES state
balloon_compaction: update the NR_BALLOON_PAGES state
meminfo: add a per node counter for balloon drivers
mm: remove references to folio in __memcg_kmem_uncharge_page()
...
Using device_create_with_groups() to simplify creation and removal.
Same as commit 1083a7be4504 ("tty: Use static attribute groups for
sysfs entries").
Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
The original version duplicated more or less the same algorithms for
both system and i/o memory.
In this version the drawing algorithms (copy/fill/blit) are separate
from the memory access (system and i/o). The two parts are getting
combined in the loadable module sources. This also makes it more robust
against wrong memory access type or alignment mistakes as there's no
direct pointer access or arithmetic in the algorithm sources anymore.
Due to liberal use of inlining the compiled result is a single function
in all 6 cases, without unnecessary function calls. Unlike earlier the
use of macros could be minimized as apparently both gcc and clang is
capable now to do the same with inline functions just as well.
What wasn't quite the same in the two variants is the support for pixel
order reversing. This version is capable to do that for both system and
I/O memory, and not only for the latter. As demand for low bits per
pixel modes isn't high there's a configuration option to enable this
separately for the CFB and SYS modules.
The pixel reversing algorithm is different than earlier and was designed
so that it can take advantage of bit order reversing instructions on
architectures which have them. And even for higher bits per pixel modes
like four bpp.
One of the shortcomings of the earlier version was the incomplete
support for foreign endian framebuffers. Now all three drawing
algorithms produce correct output on both endians with native and
foreign framebuffers. This is one of the important differences even if
otherwise the algorithms don't look too different than before.
All three routines work now with aligned native word accesses. As a
consequence blitting isn't limited to 32 bits on 64 bit architectures as
it was before.
The old routines silently assumed that rows are a multiple of the word
size. Due to how the new routines function this isn't a requirement any
more and access will be done aligned regardless. However if the
framebuffer is configured like that then some of the fast paths won't be
available.
As this code is supposed to be running on all supported architectures it
wasn't optimized for a particular one. That doesn't mean I haven't
looked at the disassembly. That's where I noticed that it isn't a good
idea to use the fallback bitreversing code for example.
The low bits per pixel modes should be faster than before as the new
routines can blit 4 pixels at a time.
On the higher bits per pixel modes I retained the specialized aligned
routines so it should be more or less the same, except on 64 bit
architectures. There the blitting word size is double now which means 32
BPP isn't done a single pixel a time now.
The code was tested on x86, amd64, mips32 and mips64. The latter two in
big endian configuration. Originally thought I can get away with the
first two, but with such bit twisting code byte ordering is tricky and
not really possible to get right without actually verifying it.
While writing such routines isn't rocket science a lot of time was spent
on making sure that pixel ordering, foreign byte order, various bits per
pixels, cpu endianness and word size will give the expected result in
all sorts of combinations without making it overly complicated or full
with special cases.
Signed-off-by: Zsolt Kajtar <soci@c64.rulez.org>
Signed-off-by: Helge Deller <deller@gmx.de>
The erase colour calculation for fbcon clearing should use get_color instead
of attr_col_ec, like everything else. The latter is similar but is not correct.
For example it's missing the depth dependent remapping and doesn't care about
blanking.
The problem can be reproduced by setting up the background colour to grey
(vt.color=0x70) and having an fbcon console set to 2bpp (4 shades of gray).
Now the background attribute should be 1 (dark gray) on the console.
If the screen is scrolled when pressing enter in a shell prompt at the bottom
line then the new line is cleared using colour 7 instead of 1. That's not
something fillrect likes (at 2bbp it expect 0-3) so the result is interesting.
This patch switches to get_color with vc_video_erase_char to determine the
erase colour from attr_col_ec. That makes the latter function redundant as
no other users were left.
Use correct erase colour for clearing in fbcon
Signed-off-by: Zsolt Kajtar <soci@c64.rulez.org>
Signed-off-by: Helge Deller <deller@gmx.de>
I was wondering why there's garbage at the bottom of the screen when
tile blitting is used with an odd mode like 1080, 600 or 200. Sure there's
only space for half a tile but the same area is clean when the buffer
is bitmap.
Then later I found that it's supposed to be cleaned but that's not
implemented. So I took what's in bitblit and adapted it for tileblit.
This implementation was tested for both the horizontal and vertical case,
and now does the same as what's done for bitmap buffers.
If anyone is interested to reproduce the problem then I could bet that'd
be on a S3 or Ark. Just set up a mode with an odd line count and make
sure that the virtual size covers the complete tile at the bottom. E.g.
for 600 lines that's 608 virtual lines for a 16 tall tile. Then the
bottom area should be cleaned.
For the right side it's more difficult as there the drivers won't let an
odd size happen, unless the code is modified. But once it reports back a
few pixel columns short then fbcon won't use the last column. With the
patch that column is now clean.
Btw. the virtual size should be rounded up by the driver for both axes
(not only the horizontal) so that it's dividable by the tile size.
That's a driver bug but correcting it is not in scope for this patch.
Implement missing margin clearing for tileblit
Signed-off-by: Zsolt Kajtar <soci@c64.rulez.org>
Signed-off-by: Helge Deller <deller@gmx.de>
With the introduction of mapping_wrprotect_range() there is no need to use
folio_mkclean() in order to write-protect mappings of frame buffer pages,
and therefore no need to inappropriately set kernel-allocated page->index,
mapping fields to permit this operation.
Instead, store the pointer to the page cache object for the mapped driver
in the fb_deferred_io object, and use the already stored page offset from
the pageref object to look up mappings in order to write-protect them.
This is justified, as for the page objects to store a mapping pointer at
the point of assignment of pages, they must all reference the same
underlying address_space object. Since the life time of the pagerefs is
also the lifetime of the fb_deferred_io object, storing the pointer here
makes sense.
This eliminates the need for all of the logic around setting and
maintaining page->index,mapping which we remove.
This eliminates the use of folio_mkclean() entirely but otherwise should
have no functional change.
[lorenzo.stoakes@oracle.com: fixup unused variable warnings]
Link: https://lkml.kernel.org/r/d4018405-2762-4385-a816-e54cc23839ac@lucifer.local
Link: https://lkml.kernel.org/r/81171ab16c14e3df28f6de9d14982cee528d8519.1739029358.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Tested-by: Kajtar Zsolt <soci@c64.rulez.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Jaya Kumar <jayakumar.lkml@gmail.com>
Cc: Maíra Canal <mcanal@igalia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Simona Vetter <simona.vetter@ffwll.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Do not select BACKLIGHT_CLASS_DEVICE from FB_BACKLIGHT. The latter
only controls backlight support within fbdev core code and data
structures.
Make fbdev drivers depend on BACKLIGHT_CLASS_DEVICE and let users
select it explicitly. Fixes warnings about recursive dependencies,
such as
error: recursive dependency detected!
symbol BACKLIGHT_CLASS_DEVICE is selected by FB_BACKLIGHT
symbol FB_BACKLIGHT is selected by FB_SH_MOBILE_LCDC
symbol FB_SH_MOBILE_LCDC depends on FB_DEVICE
symbol FB_DEVICE depends on FB_CORE
symbol FB_CORE is selected by DRM_GEM_DMA_HELPER
symbol DRM_GEM_DMA_HELPER is selected by DRM_PANEL_ILITEK_ILI9341
symbol DRM_PANEL_ILITEK_ILI9341 depends on BACKLIGHT_CLASS_DEVICE
BACKLIGHT_CLASS_DEVICE is user-selectable, so making drivers adapt to
it is the correct approach in any case. For most drivers, backlight
support is also configurable separately.
v3:
- Select BACKLIGHT_CLASS_DEVICE in PowerMac defconfigs (Christophe)
- Fix PMAC_BACKLIGHT module dependency corner cases (Christophe)
v2:
- s/BACKLIGHT_DEVICE_CLASS/BACKLIGHT_CLASS_DEVICE (Helge)
- Fix fbdev driver-dependency corner case (Arnd)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20241216074450.8590-2-tzimmermann@suse.de
Break the for loop immediately upon finding the target, making the
process more efficient.
Signed-off-by: Qianqiang Liu <qianqiang.liu@163.com>
Signed-off-by: Helge Deller <deller@gmx.de>
