Commit Graph

1464954 Commits

Author SHA1 Message Date
Miro Kropacek
d7dda89ad0 fbdev: atafb: Give atafb proper parent
The atafb fb device registers no parent, causing a missing symlink
(/sys/class/graphics/fb0/device). Xorg fbdevhw driver looks for that
symlink when scanning for devices, so add a parent node for atafb.

The proper way to do that is use of framebuffer_alloc(), which
requries refactoring atafb to move from static fb_info to allocation
of fb_info by framebuffer_alloc().
About the only location where a fb_info pointer cannot be passed
is monspec setup in atafb_setup(). Store static monspecs there
and copy into place after framebuffer_alloc().

Pass fb_info everywhere it's needed (detect, decode_var and
do_fb_set_var functions), and remove the static fb_info struct.

Signed-off-by: Miro Kropacek <miro.kropacek@gmail.com>
Reviewed-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>
Link: https://lists.debian.org/debian-68k/2026/08/msg00000.html
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-21 00:02:41 +02:00
Runyu Xiao
f8e43fe0f2 fbdev: omapfb: panel-dsi-cm: initialize lock before registering display
dsicm_probe() registers the display before initializing ddata->lock.
Once omapdss_register_display() publishes the display, another consumer
can reach a dsicm callback that takes this mutex while it is still
uninitialized.

Initialize the mutex before registering the display so the published
callbacks always see a valid lock.

Fixes: f76ee892a9 ("omapfb: copy omapdss & displays for omapfb")
Cc: stable@vger.kernel.org
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-20 23:45:07 +02:00
Ajith P V
f74cf70e5e fbdev: viafb: refactor strcpy and viafb_name
Eliminate the single-use file-scope variable `viafb_name` and pass the
"Via" string literal directly to strcpy().

Since "Via" is a literal constant, the compiler safely executes
compile-time bounds checking during fortify verification. This satisfies
the security initiative requirements while minimizing code complexity.

Signed-off-by: Ajith P V <ajithpv.linux@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-20 23:45:07 +02:00
BingKun Yue
ba13226fc9 fbdev: platinumfb: add error checking for ioremap calls
The ioremap() and ioremap_wt() calls in platinumfb_probe() were not
checked for failure. If any of these mappings fail, the driver would
dereference NULL pointers, leading to a kernel panic.

Add proper error checking and use goto-based cleanup to avoid code
duplication across the error paths.

Signed-off-by: BingKun Yue <yuebingkun@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-20 23:45:07 +02:00
Randy Dunlap
772bd1a842 fbdev: maxine: use MODULE_LICENSE() unconditionally
This driver cannot be built as a loadable module so testing for
"#ifdef MODULE" is not appropriate here.
Also, MODULE_LICENSE() is always available.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-20 23:45:07 +02:00
Randy Dunlap
c761c0400f fbdev: maxine: fix maxinefb_init() return value
A driver should return a negative error code on failure of its
module_init() function so that the system recognizes the failure.
Change the "return 1" to "return -ENODEV".

Suggested-by: sashiko-bot@kernel.org
Link: https://sashiko.dev/#/patchset/20260809234810.982500-1-rdunlap@infradead.org?part=1
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-20 23:45:07 +02:00
Randy Dunlap
3adec5c640 fbdev: maxine: fix 64-bit build error
The KSEG1ADDR() macro is only defined for non-64BIT builds.
Use the CKSEG1ADDR() macro instead.

In file included from ../drivers/video/fbdev/maxinefb.c:34:
../drivers/video/fbdev/maxinefb.c: In function 'maxinefb_ims332_write_register':
../include/video/maxinefb.h:16:41: error: implicit declaration of function 'KSEG1ADDR'; did you mean 'CKSEG1ADDR'? [-Wimplicit-function-declaration]
   16 | #define MAXINEFB_IMS332_ADDRESS         KSEG1ADDR(0x1c140000)
../drivers/video/fbdev/maxinefb.c:66:49: note: in expansion of macro 'MAXINEFB_IMS332_ADDRESS'
   66 |         register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;
../drivers/video/fbdev/maxinefb.c:66:40: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
   66 |         register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-20 23:45:07 +02:00
Randy Dunlap
47eb05e731 fbdev: maxine: elide an unused function
maxinefb_ims332_read_register() is not used, but since it describes a
hardware interface, leave it in the source file as documentation
and surround it inside an #if 0/#endif block.

../drivers/video/fbdev/maxinefb.c:74:21: warning: 'maxinefb_ims332_read_register' defined but not used [-Wunused-function]
   74 | static unsigned int maxinefb_ims332_read_register(int regno)

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-20 23:45:06 +02:00
Randy Dunlap
311f2c770d fbdev: maxine: make functions static
Make 3 functions static so that they don't need to be declared in a
header file.

../drivers/video/fbdev/maxinefb.c:64:6: warning: no previous prototype for 'maxinefb_ims332_write_register' [-Wmissing-prototypes]
   64 | void maxinefb_ims332_write_register(int regno, register unsigned int val)
../drivers/video/fbdev/maxinefb.c:74:14: warning: no previous prototype for 'maxinefb_ims332_read_register' [-Wmissing-prototypes]
   74 | unsigned int maxinefb_ims332_read_register(int regno)
../drivers/video/fbdev/maxinefb.c:114:12: warning: no previous prototype for 'maxinefb_init' [-Wmissing-prototypes]
  114 | int __init maxinefb_init(void)

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-20 23:45:06 +02:00
Shixiong Ou
27c97be7f3 fbdev: atyfb: Convert to managed PCI and ioremap API
Fix missing pci_disable_device() in probe and remove.

Use pcim_enable_device(), pcim_request_region(), devm_ioremap(),
devm_ioremap_uc() and devm_ioremap_wc() for the PCI path. Convert
aux_start to devm_request_mem_region(). Guard atyfb_remove() to
only unmap/release for non-PCI (Atari) devices. Keep iounmap for
sprite.addr outside the guard since it uses raw ioremap().

Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-15 10:40:58 +02:00
Shixiong Ou
b2c3a91e2b fbdev: matrox: Convert to managed PCI and ioremap API
Fix missing pci_disable_device() in probe and remove.

Use pcim_enable_device(), devm_request_mem_region(),
devm_ioremap() and devm_ioremap_wc() to replace manual resource
management. Remove all release_mem_region() and iounmap() calls.
Use devm_request_mem_region() instead of pcim_request_region()
because the requested sizes (16384 for MMIO, maxvram for FB) do
not match the full PCI BAR sizes.

Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-15 10:40:58 +02:00
Shixiong Ou
d37b232649 fbdev: savage: Convert to managed PCI and ioremap API
Fix missing pci_disable_device() in probe and remove.

Use pcim_enable_device(), pcim_request_all_regions(),
devm_ioremap() and devm_ioremap_wc() to replace manual resource
management. Remove all pci_release_regions() and iounmap() calls.
Merge failed_init label into failed_enable.

Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-15 10:40:57 +02:00
Shixiong Ou
a41961f364 fbdev: nvidia: Convert to managed PCI and ioremap API
Fix missing pci_disable_device() in probe and remove.

Use pcim_enable_device(), pcim_request_all_regions(),
devm_ioremap() and devm_ioremap_wc() to replace manual resource
management. Remove all pci_release_regions() and iounmap() calls.

Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-15 10:40:57 +02:00
Shixiong Ou
e36aa3669e fbdev: aty128fb: Convert to managed PCI and ioremap API
Fix missing pci_disable_device() in probe and remove.

Use pcim_enable_device(), pcim_request_region(), devm_ioremap()
and devm_ioremap_wc() to replace manual resource management.
Remove all release_mem_region() and iounmap() calls.

Signed-off-by: Shixiong Ou <oushixiong@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-15 10:40:57 +02:00
Karl Mehltretter
39dd7598fb fbdev: clps711x-fb: Remove unreachable unregister_framebuffer() call
The unregister_framebuffer() call in clps711x_fb_probe() is unreachable.
register_framebuffer() failure jumps to the unwind label, while success
returns immediately.

Remove it.

Found with Clang's -Wunreachable-code.

Fixes: 36462ac193 ("fbdev: clps711x-fb: Replace check_fb in favor of struct fb_info.lcd_dev")
Assisted-by: Claude:claude-fable-5
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Helge Deller
4c1977df69 fbdev: mb862xxfb: Silence possibly unused functions
When CONFIG_PCI=n, the kernel test robot reports that on powerpc some
functions and variables may possibly be unused. Silence those warnings.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202608081537.o23Goj8d-lkp@intel.com/
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Helge Deller
de508ece1d sticon/parisc: Detect default STI graphics card for console output
If a machine has multiple graphic cards, detect the graphic card which is used
to display firmware messages and use that one as the default graphic card for
sticon and fbcon.

On parisc machines the default graphic card used for BCH (boot console
handler, aka BIOS menu) is stored in the stable storage (equivalent to CMOS
storage on x86) or in the console path in page zero. Extract that path and
store it as default STI path for later comparism. Take care that the graphic
card can be a GSC or a PCI card which use different path strings.

Increase max string size for default_sti_path to 32 chars as the
print_pa_hwpath() function formats a hardware path using unbounded sprintf
calls for up to 6 bus converter components and 1 module component (e.g.,
255/255/...), which can produce a string up to 28 bytes long.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
2026-08-10 08:13:26 +02:00
Hui Su
9ad709afdf fbdev: ssd1307fb: defer I2C transfers from damage callbacks
The fbdev damage callbacks may run from fbcon while printk has disabled
preemption.  They currently update the display synchronously, which enters
the sleeping I2C transfer path from atomic context.

A complete report from an RK3566 system follows:

  [  258.129004] watchdog: watchdog0: watchdog did not stop!
  [  258.129067] BUG: scheduling while atomic: systemd/1/0x00000003
  [  258.129076] Modules linked in: algif_hash algif_skcipher af_alg bnep
  binfmt_misc lz4hc lz4 zram snd_soc_hdmi_codec brcmfmac_wcc hci_uart
  fb_ssd1306(C) fbtft(C) btqca btrtl btintel btsdio snd_soc_simple_card
  motorcomm pwm_fan snd_soc_simple_card_utils ssd130x_spi nls_iso8859_1
  ssd130x btbcm drm_shmem_helper display_connector brcmfmac ssd1307fb
  brcmutil bluetooth cfg80211 rfkill snd_soc_rockchip_i2s_tdm
  snd_soc_rk817 hantro_vpu snd_soc_core snd_compress snd_pcm_dmaengine
  v4l2_vp9 snd_pcm v4l2_h264 rockchip_rga snd_timer rk_crypto2
  spi_rockchip_sfc videobuf2_dma_contig snd sm3_generic v4l2_mem2mem
  videobuf2_dma_sg dwmac_rk sm3 soundcore videobuf2_memops videobuf2_v4l2
  stmmac_platform dw_hdmi_cec videodev videobuf2_common dw_hdmi_i2s_audio
  stmmac rk817_charger pcs_xpcs mc cpufreq_dt sch_fq_codel ip_tables
  x_tables autofs4
  [  258.129215] Preemption disabled at:
  [  258.129216] [<ffff80008012f96c>] vprintk_emit+0x11c/0x340
  [  258.129234] CPU: 0 PID: 1 Comm: systemd Tainted: G         C
  6.6.0-rc5-rockchip-rk356x #4
  [  258.129239] Hardware name: Rockchip RK3566 OPi 3B (DT)
  [  258.129243] Call trace:
  [  258.129245]  dump_backtrace+0xa0/0x128
  [  258.129252]  show_stack+0x20/0x38
  [  258.129256]  dump_stack_lvl+0x60/0xb0
  [  258.129265]  dump_stack+0x18/0x28
  [  258.129269]  __schedule_bug+0xa0/0xc8
  [  258.129274]  __schedule+0x9ac/0xd30
  [  258.129279]  schedule+0x60/0x100
  [  258.129282]  schedule_timeout+0x194/0x338
  [  258.129289]  rk3x_i2c_xfer_common.isra.0+0x384/0x498
  [  258.129296]  rk3x_i2c_xfer+0x20/0x60
  [  258.129300]  __i2c_transfer+0x194/0x648
  [  258.129308]  i2c_transfer+0x9c/0x130
  [  258.129313]  i2c_transfer_buffer_flags+0x64/0x98
  [  258.129318]  ssd1307fb_update_rect+0x42c/0x560 [ssd1307fb]
  [  258.129334]  ssd1307fb_defio_imageblit+0x34/0x50 [ssd1307fb]
  [  258.129343]  soft_cursor+0x13c/0x210
  [  258.129350]  bit_cursor+0x2dc/0x550
  [  258.129354]  fbcon_cursor+0xec/0x108
  [  258.129359]  hide_cursor+0x44/0xc8
  [  258.129365]  vt_console_print+0x398/0x3b0
  [  258.129370]  console_flush_all.isra.0+0x17c/0x410
  [  258.129377]  console_unlock+0x4c/0x100
  [  258.129382]  vprintk_emit+0x1c8/0x340
  [  258.129386]  vprintk_default+0x40/0x58
  [  258.129389]  vprintk+0xb8/0xd0
  [  258.129392]  _printk+0x68/0x98
  [  258.129398]  watchdog_release+0x170/0x230
  [  258.129404]  __fput+0xbc/0x288
  [  258.129409]  __fput_sync+0x58/0x70
  [  258.129413]  __arm64_sys_close+0x40/0x90
  [  258.129419]  invoke_syscall+0x4c/0x118
  [  258.129426]  el0_svc_common.constprop.0+0x48/0xf0
  [  258.129432]  do_el0_svc+0x24/0x38
  [  258.129437]  el0_svc+0x48/0x100
  [  258.129443]  el0t_64_sync_handler+0xc0/0xc8
  [  258.129448]  el0t_64_sync+0x190/0x198
  [  258.573087] ------------[ cut here ]------------
  [  258.573098] DEBUG_LOCKS_WARN_ON(val > preempt_count())
  [  258.573111] WARNING: CPU: 0 PID: 1 at kernel/sched/core.c:5871
  preempt_count_sub+0x9c/0x148
  [  258.573130] Modules linked in: algif_hash algif_skcipher af_alg bnep
  binfmt_misc lz4hc lz4 zram snd_soc_hdmi_codec brcmfmac_wcc hci_uart
  fb_ssd1306(C) fbtft(C) btqca btrtl btintel btsdio snd_soc_simple_card
  motorcomm pwm_fan snd_soc_simple_card_utils ssd130x_spi nls_iso8859_1
  ssd130x btbcm drm_shmem_helper display_connector brcmfmac ssd1307fb
  brcmutil bluetooth cfg80211 rfkill snd_soc_rockchip_i2s_tdm
  snd_soc_rk817 hantro_vpu snd_soc_core snd_compress snd_pcm_dmaengine
  v4l2_vp9 snd_pcm v4l2_h264 rockchip_rga snd_timer rk_crypto2
  spi_rockchip_sfc videobuf2_dma_contig snd sm3_generic v4l2_mem2mem
  videobuf2_dma_sg dwmac_rk sm3 soundcore videobuf2_memops videobuf2_v4l2
  stmmac_platform dw_hdmi_cec videodev videobuf2_common dw_hdmi_i2s_audio
  stmmac rk817_charger pcs_xpcs mc cpufreq_dt sch_fq_codel ip_tables
  x_tables autofs4
  [  258.573268] CPU: 0 PID: 1 Comm: systemd Tainted: G        WC
  6.6.0-rc5-rockchip-rk356x #4
  [  258.573274] Hardware name: Rockchip RK3566 OPi 3B (DT)
  ** 37 printk messages dropped **
  [  258.574064] Preemption disabled at:
  ** 42 printk messages dropped **
  [  259.190237] Preemption disabled at:

Track damage in the driver's private data under a spinlock and merge
multiple updates into a bounding rectangle.  Queue the existing
deferred-I/O work immediately for damage reported by fbdev drawing and
write helpers, so allocation and I2C transfers run from process context
without adding the configured mmap refresh delay.  Keep full-screen
updates for dirty mmap pages, for which no precise rectangle is available.

Tested on an RK3566 board with a 128x64 OLED by running five rounds of 250
KERN_EMERG messages in total while issuing framebuffer writes every 15 ms.
No atomic-sleep, preemption, or lockdep warning occurred.  Kprobe tracing
also confirmed that cursor-only damage remained an 8x16 partial update.

Fixes: a2ed00da50 ("drivers/video: add support for the Solomon SSD1307 OLED Controller")
Cc: stable@vger.kernel.org
Signed-off-by: Hui Su <sh_def@163.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Julia Lawall
49e4950e17 fbdev: au1100fb: drop unneeded semicolon
When a function-like macro expands to an expression, that expression
doesn't need a semicolon after it.  All uses have been verified to
have their own semicolons.

This was found using the following Coccinelle semantic patch:

@r@
identifier i : script:ocaml() { String.lowercase_ascii i = i };
expression e;
@@

*#define i(...) e;

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Daniel Palmer
0fc41be57d fbdev: tdfxfb: Program the initial video mode
If the card does not get bound to by fbcon set_par() never happens
and the initial video mode is not setup and the display detects
no signal.

Program the video mode and also clear the framebuffer memory so
random garbage isn't displayed.

Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Daniel Palmer
edfbc5d2ad fbdev: tdfxfb: Wake the VGA core before programming the CRTC
If the card was unbooted the VGA core needs to be woken up before
poking at it.

Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Daniel Palmer
08364e38de fbdev: tdfxfb: Manually boot unbooted cards
If the card is detected as being unbooted it isn't too difficult
to use the config table in its BIOS to fire it up so do it.

Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Daniel Palmer
28c1d44af6 fbdev: tdfxfb: Attempt to detect if the card wasn't booted
Until now a card had to have been booted by its video BIOS
otherwise the driver would probe, create the fb etc but there
would be no output on the display.

There doesn't seem to be a documented way work out if the BIOS
ran or not. Checking if the values in registers match what is
in the config table in the BIOS seems to be the only option.

On my 16MB Voodoo 3 3000 checking the contents of the draminit0
register versus what is in the config table seems to be enough.

Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Daniel Palmer
ff21ab0101 fbdev: tdfxfb: Add helper to read config table from BIOS
In the case that the video BIOS didn't run because the card isn't the
primary card, the BIOS doesn't support running old skool video BIOS
(modern BIOS without CSM), or the machine isn't x86 it needs to be
booted manually. To do this the config table in the BIOS is needed.

Add a helper to get the config table in preparation for manually
booting cards.

Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Mingyu Wang
27b8e3c27d fbdev: core: Clamp total_size to smem_len in read/write functions
Some legacy fbdev drivers may incorrectly set info->screen_size to a
value larger than the actual mapped framebuffer size (info->fix.smem_len)
during mode switches. This could allow out-of-bounds I/O and system
memory accesses in fb_io_read(), fb_io_write(), fb_sys_read(), and
fb_sys_write().

Prevent this by clamping total_size to smem_len when smem_len is non-zero.
Virtual framebuffers (smem_len == 0) are unaffected.

This is a hardening measure; no specific crash is fixed by this patch.

Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:26 +02:00
Danila Chernetsov
7b5c7bc55e fbdev: kyro: Validate overlay viewport coordinates
The overlay viewport end coordinates are computed from the viewport
origin and dimensions using 32-bit unsigned arithmetic. Large input
values can cause these calculations to wrap around before the resulting
coordinates are passed to SetOverlayViewPort().

SetOverlayViewPort() packs the viewport coordinates into 16-bit
register fields. The X coordinates are additionally adjusted by +2
and +1 before being written. Validate the coordinate calculations
for 32-bit wraparound and ensure that the adjusted coordinates fit
within their 16-bit register fields before calling
SetOverlayViewPort().

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Danila Chernetsov <listdansp@mail.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Julian Braha
d1917ccb7b fbdev: mb862xx: replace dead select with dependency
'select' does not work on config options in a 'choice', so currently it is
possible to enable FB_MB862XX_LIME without FB_LITTLE_ENDIAN.

We cannot replace the 'select FB_LITTLE_ENDIAN' without also changing
FB_FOREIGN_ENDIAN from 'select' to 'depends on', otherwise we will get
a recursive dependency.

Since the default choice is FB_BOTH_ENDIAN, let's use:
'depends on FB_LITTLE_ENDIAN || FB_BOTH_ENDIAN'
to avoid breaking defconfig.

This dead select was found by kconfirm, a static analysis tool for Kconfig.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Julian Braha <julianbraha@gmail.com>
Link: https://lore.kernel.org/all/20260722220023.196029-1-julianbraha@gmail.com/
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pan Chuang
fa1005144f fbdev: sa1100fb: Remove redundant dev_err()
Since commit 55b48e23f5 ("genirq/devres: Add error handling in
devm_request_*_irq()"), devm_request_irq() automatically logs
detailed error messages on failure. Remove the now-redundant
driver-specific dev_err() call.

Signed-off-by: Pan Chuang <panchuang@vivo.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pan Chuang
1867db62c1 fbdev: s3c-fb: Remove redundant dev_err()
Since commit 55b48e23f5 ("genirq/devres: Add error handling in
devm_request_*_irq()"), devm_request_irq() automatically logs
detailed error messages on failure. Remove the now-redundant
driver-specific dev_err() call.

Signed-off-by: Pan Chuang <panchuang@vivo.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pan Chuang
24eadacc51 fbdev: pxafb: Remove redundant dev_err()
Since commit 55b48e23f5 ("genirq/devres: Add error handling in
devm_request_*_irq()"), devm_request_irq() automatically logs
detailed error messages on failure. Remove the now-redundant
driver-specific dev_err() call.

Signed-off-by: Pan Chuang <panchuang@vivo.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pan Chuang
1f2b187074 fbdev: pxa3xx-gcu: Remove redundant dev_err()
Since commit 55b48e23f5 ("genirq/devres: Add error handling in
devm_request_*_irq()"), devm_request_irq() automatically logs
detailed error messages on failure. Remove the now-redundant
driver-specific dev_err() call.

Signed-off-by: Pan Chuang <panchuang@vivo.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pan Chuang
dde94092ec fbdev: pxa168fb: Remove redundant dev_err()
Since commit 55b48e23f5 ("genirq/devres: Add error handling in
devm_request_*_irq()"), devm_request_irq() automatically logs
detailed error messages on failure. Remove the now-redundant
driver-specific dev_err() call.

Signed-off-by: Pan Chuang <panchuang@vivo.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pan Chuang
3c82279841 fbdev: omapfb/dsi-cm: Remove redundant dev_err()
Since commit 55b48e23f5 ("genirq/devres: Add error handling in
devm_request_*_irq()"), devm_request_irq() automatically logs
detailed error messages on failure. Remove the now-redundant
driver-specific dev_err() call.

Signed-off-by: Pan Chuang <panchuang@vivo.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pan Chuang
87a1bc216d fbdev: mmp: Remove redundant dev_err()
Since commit 55b48e23f5 ("genirq/devres: Add error handling in
devm_request_*_irq()"), devm_request_irq() automatically logs
detailed error messages on failure. Remove the now-redundant
driver-specific dev_err() call.

Signed-off-by: Pan Chuang <panchuang@vivo.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Randy Dunlap
048ad864d6 fonts: fixup font.h kernel-doc warnings
Use the typedef keyword when describing a typedef.
Add the missing function return value for font_glyph_size().

Warning: include/linux/font.h:84 cannot understand function prototype:
  'typedef const unsigned char font_data_t;'
Warning: include/linux/font.h:53 No description found for return value
  of 'font_glyph_size'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: stable@vger.kernel.org # v7.1+
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Florian Fuchs
5dc2e70dd7 fbdev: pvr2fb: correct user pointer annotation and sentinel initializer
Add __user annotation to buf, as it is passed as a user pointer in
pin_user_pages_fast(). Use an empty initializer for the sentinel
board-table entry to avoid initializing a function pointer with an
integer literal.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202607131247.fpQ6eTc7-lkp@intel.com/
Cc: stable@vger.kernel.org
Signed-off-by: Florian Fuchs <fuchsfl@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pengpeng Hou
3cc2fad376 fbdev: udlfb: validate vendor descriptor items
dlfb_parse_vendor_descriptor() walks key-length-value items inside the
DisplayLink vendor descriptor.

Require each item to contain its key, length and declared value bytes
before reading item-specific fields such as max_area.

Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Pengpeng Hou
74c09634a5 fbdev: sstfb: add missing MODULE_DEVICE_TABLE()
The driver has a match table for the pci bus wired into its driver
structure, but the table is not exported with MODULE_DEVICE_TABLE().

Add the missing MODULE_DEVICE_TABLE() entry so module alias information
is generated for automatic module loading.

This is a source-level fix.  It does not claim dynamic hardware
reproduction; the evidence is the driver-owned match table, its use by
the driver registration structure, and the missing module alias
publication.

Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Andreas Kemnade
31875c51c3 fbdev: omap2: dsi: do not copy isr table
To te able to unregister stuff from isrs, the corresponding table was
copied.  Nobody seems to unregister stuff that way, so it does not help.
But there are stack-allocated objects passed to these isrs giving chances
of UAF of these objects if irqs are unregistered while they are handled,
so better do not copy that table.

Suggested-by: sashiko-bot@kernel.org
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Myeonghun Pak
95a627143a fbdev: tdfxfb: fix PCI enable cleanup with pcim_enable_device()
tdfxfb_probe() enables the PCI device with pci_enable_device(), but
several failure paths after that point return without disabling it. The
framebuffer_alloc() failure path returns -ENOMEM directly, and the later
shared out_err path releases the framebuffer and returns -ENXIO without
balancing the PCI enable state.

The successful probe path has the same imbalance because tdfxfb_remove()
releases the framebuffer, mappings and regions, but never calls
pci_disable_device().

Use pcim_enable_device() so the PCI device is disabled automatically on
probe failure and driver detach.

This issue was identified during our ongoing static-analysis research while
reviewing kernel code.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Myeonghun Pak
de8db23aa7 fbdev: uvesafb: unregister connector callback on init failure
uvesafb_init() registers the v86d connector callback before registering
the platform driver. If platform_driver_register() fails, the function
returns the error directly and leaves the connector callback registered.

The later platform-device failure path already unregisters the callback.
Add the same cleanup before the final return when platform-driver
registration fails.

This issue was identified during our ongoing static-analysis research while
reviewing kernel code.

Fixes: 8bdb3a2d7d ("uvesafb: the driver core")
Cc: stable@vger.kernel.org
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-10 08:13:25 +02:00
Linus Torvalds
db2ddb8714 Linux 7.2-rc7 2026-08-09 14:54:50 -07:00
Linus Torvalds
b9b3e33b70 tracing fixes for 7.2:
- Fix use-after-free in eventfs_remove_rec()
 
   The freeing of the eventfs_inode children used list_for_each_entry() where
   the child is freed via srcu, but there's still a chance that it gets freed.
   It should be using list_for_each_entry_safe().
 
 - Fix eventfs_inode SRCU use of list in freeing
 
   The iterator uses an SRCU protected list walk on the eventfs inodes. The
   eventfs inode uses its "list" field in a union with the RCU list head.
   When the inode gets added to the SRCU list it immediately corrupts the
   list pointer and can cause an issue with the iterator. Move the RCU list
   head to be shared with the children list head which allows the iterator to
   check the parent inode if is freed before referencing the child. Have the
   iterator check the parent "is_freed" field and break out if it is set.
   Also add memory barriers to make sure the ordering is correct.
 
 - Fix various RCU synchronization issues with direct_functions
 
   Updates to direct_functions have some missing RCU protection and
   synchronization. Restructure the code a bit to make sure updates to the
   direct_functions are protected.
 
 - Remove an unneeded comma from a scope_guard()
 
   There's a spurious comma in a scope_guard(). Remove it.
 
 - Fix race in per CPU buffer swap in the ring buffer
 
   When a per CPU buffer swap happens, it must make sure that it doesn't
   occur while a writer is active. Instead it returns an -EBUSY. But there's
   a small race window when a writer moves from one sub-buffer to the next
   that it resets the "committing" counter. If a swap happens at that moment,
   the buffer used for the commit of an event will not match the buffer the
   event is actually on. Instead of using the "committing" counter, use the
   recursive detection counter that does not get reset when the writer
   crosses sub-buffers.
 
 - Fix off-by-one in ftrace_free_mem()
 
   The function ftrace_free_mem() gets an "end_ptr" as a parameter that is
   exclusive to the rang to be freed. But its value is used to search for the
   records that expects an inclusive value. Subtract one from the parameter
   to convert it to an inclusive range.
 
 - Disable resizing of the ring buffer for persistent buffers
 
   Resizing the persistent buffer has undefined behavior. Prevent it from
   being resized.
 
 - Disable changing ring buffer subbuf order when resizing is disabled
 
   The ring buffer subbuffer order can not be changed during resizing. Use
   that instead of just checking if the buffer is mapped as mapped buffers
   also have resizing disabled.
 
 - Initialize subbuf_order of reader pages when they are created
 
   In rb_allocate_cpu_buffer() the bpage->order is not updated to the current
   subbuf_order leaving it as zero. This value is used when the page is freed.
 
 - Fix test_ringbuffer() to test for ERR_PTR before calling kthread_stop()
 
   The rb_threads[] array is assigned the output of kthread_run_on_cpu()
   which could return an ERR_PTR. At the end of the test, all threads in the
   array are cleaned up by kthread_stop() passing in the value in the array
   if it isn't zero. But if the array contains an ERR_PTR, kthread_stop()
   will not be able to handle it properly.
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Merge tag 'trace-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix use-after-free in eventfs_remove_rec()

   The freeing of the eventfs_inode children used list_for_each_entry()
   where the child is freed via srcu, but there's still a chance that it
   gets freed. It should be using list_for_each_entry_safe().

 - Fix eventfs_inode SRCU use of list in freeing

   The iterator uses an SRCU protected list walk on the eventfs inodes.
   The eventfs inode uses its "list" field in a union with the RCU list
   head. When the inode gets added to the SRCU list it immediately
   corrupts the list pointer and can cause an issue with the iterator.
   Move the RCU list head to be shared with the children list head which
   allows the iterator to check the parent inode if is freed before
   referencing the child. Have the iterator check the parent "is_freed"
   field and break out if it is set. Also add memory barriers to make
   sure the ordering is correct.

 - Fix various RCU synchronization issues with direct_functions

   Updates to direct_functions have some missing RCU protection and
   synchronization. Restructure the code a bit to make sure updates to
   the direct_functions are protected.

 - Remove an unneeded comma from a scope_guard()

   There's a spurious comma in a scope_guard(). Remove it.

 - Fix race in per CPU buffer swap in the ring buffer

   When a per CPU buffer swap happens, it must make sure that it doesn't
   occur while a writer is active. Instead it returns an -EBUSY. But
   there's a small race window when a writer moves from one sub-buffer
   to the next that it resets the "committing" counter. If a swap
   happens at that moment, the buffer used for the commit of an event
   will not match the buffer the event is actually on. Instead of using
   the "committing" counter, use the recursive detection counter that
   does not get reset when the writer crosses sub-buffers.

 - Fix off-by-one in ftrace_free_mem()

   The function ftrace_free_mem() gets an "end_ptr" as a parameter that
   is exclusive to the rang to be freed. But its value is used to search
   for the records that expects an inclusive value. Subtract one from
   the parameter to convert it to an inclusive range.

 - Disable resizing of the ring buffer for persistent buffers

   Resizing the persistent buffer has undefined behavior. Prevent it
   from being resized.

 - Disable changing ring buffer subbuf order when resizing is disabled

   The ring buffer subbuffer order can not be changed during resizing.
   Use that instead of just checking if the buffer is mapped as mapped
   buffers also have resizing disabled.

 - Initialize subbuf_order of reader pages when they are created

   In rb_allocate_cpu_buffer() the bpage->order is not updated to the
   current subbuf_order leaving it as zero. This value is used when the
   page is freed.

 - Fix test_ringbuffer() to test for ERR_PTR before calling
   kthread_stop()

   The rb_threads[] array is assigned the output of kthread_run_on_cpu()
   which could return an ERR_PTR. At the end of the test, all threads in
   the array are cleaned up by kthread_stop() passing in the value in
   the array if it isn't zero. But if the array contains an ERR_PTR,
   kthread_stop() will not be able to handle it properly.

* tag 'trace-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Fix crash passing ERR_PTR to kthread_stop()
  ring-buffer: Initialise reader page order in rb_allocate_cpu_buffer()
  ring-buffer: Prevent subbuf order change when resizing is disabled
  ring-buffer: Prevent resizing of persistent ring buffer
  ftrace: Fix off-by-one fentry site disable in ftrace_free_mem()
  ring-buffer: Use current_context for safe per-CPU buffer swap
  ftrace: Drop extra comma in trace_buffered_event_enable
  ftrace: Protect direct_functions in update_ftrace_direct_mod
  ftrace: Protect direct_functions in update_ftrace_direct_del
  ftrace: Protect direct_functions in ftrace_find_rec_direct
  eventfs: Use children field for rcu head and add memory barriers
  eventfs: Fix use-after-free in eventfs_remove_rec()
2026-08-09 08:47:31 -07:00
Linus Torvalds
b643e495ae s390 updates for 7.2-rc7
- Fix potential uninitialized memory reads and buffer overflows from
   malformed zcrypt CCA and EP11 requests by properly validating lengths
   and payloads
 
 - Fix possible out of bounds accesses in zcrypt EP11 domain handling by
   replacing fixed payload layout assumptions with parsing ASN.1 fields
   with bounds checks
 
 - Fix zcrypt CCA and EP11 request and reply buffer allocations missing
   required 4-byte padding, and scrub the full allocation on release
 
 - Fix zcrypt CCA and EP11 messages leaking up to 3 uninitialized bytes
   of memory by zeroing trailing alignment padding
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Merge tag 's390-7.2-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Vasily Gorbik:

 - Fix potential uninitialized memory reads and buffer overflows from
   malformed zcrypt CCA and EP11 requests by properly validating lengths
   and payloads

 - Fix possible out of bounds accesses in zcrypt EP11 domain handling by
   replacing fixed payload layout assumptions with parsing ASN.1 fields
   with bounds checks

 - Fix zcrypt CCA and EP11 request and reply buffer allocations missing
   required 4-byte padding, and scrub the full allocation on release

 - Fix zcrypt CCA and EP11 messages leaking up to 3 uninitialized bytes
   of memory by zeroing trailing alignment padding

* tag 's390-7.2-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/zcrypt: Pad trailing CCA or EP11 message with zeros
  s390/zcrypt: Improve EP11 CPRB domain handling with ASN.1 parsing
  s390/zcrypt: Improve EP11 CPRB length and overflow checks
  s390/zcrypt: Improve CCA CPRB length and overflow checks
  s390/zcrypt: Fix CPRB memory allocation in zcrypt misc code
2026-08-09 06:31:16 -07:00
Hui Su
91542863ab ring-buffer: Fix crash passing ERR_PTR to kthread_stop()
In test_ringbuffer()'s out_free cleanup loop, the check
`!rb_threads[cpu]` only catches NULL entries and misses entries that
hold an ERR_PTR.

rb_threads[] is static, so unassigned slots are NULL. But when
kthread_run_on_cpu() fails for a cpu, it stores ERR_PTR(-ENOMEM) (or
-EINTR) in rb_threads[cpu] before the creation loop jumps to out_free.
That entry is non-NULL, so the old `!ptr` check does not break, and the
cleanup proceeds to call kthread_stop() on the ERR_PTR. kthread_stop()
then dereferences the bogus pointer, crashing the kernel during the
late_initcall self-test.

crash logs:
  BUG: kernel NULL pointer dereference, address: 000000000000001c
  Oops: 0002 [#1] SMP NOPTI
  CPU: 1 PID: 1 Comm: swapper/0 Not tainted 7.2.0-rc6-dirty #7 PREEMPT(lazy)
  RIP: 0010:kthread_stop+0x2e/0x220
  RBX: fffffffffffffff4
  CR2: 000000000000001c
  Call Trace:
   <TASK>
   test_ringbuffer+0x1ec/0x650
   do_one_initcall+0x6c/0x2c0
   kernel_init_freeable+0x21d/0x420
   kernel_init+0x15/0x1c0
   ret_from_fork+0x21b/0x320
   </TASK>
  Kernel panic - not syncing: Fatal exception

Cc: stable@vger.kernel.org
Fixes: 64ed3a049e ("ring-buffer: make use of the helper function kthread_run_on_cpu()")
Link: https://patch.msgid.link/20260807154145.2846521-2-sh_def@163.com
Signed-off-by: Hui Su <sh_def@163.com>
Reviewed-by: Vincent Donnefort <vdonnefort@google.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:26:30 -04:00
Vincent Donnefort
6d014e44b6 ring-buffer: Initialise reader page order in rb_allocate_cpu_buffer()
In rb_allocate_cpu_buffer(), bpage->order was omitted, leaving it as 0.
This is an issue for a ring-buffer with subbufs bigger than PAGE_SIZE if
when freed: free_buffer_page() relies on this value. Align the value
with the actual allocation size (buffer::subbuf_order).

Cc: stable@vger.kernel.org
Fixes: f9b94daa54 ("ring-buffer: Set new size of the ring buffer sub page")
Link: https://patch.msgid.link/20260806211306.3704194-4-vdonnefort@google.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:26:11 -04:00
Vincent Donnefort
bf98d7b0d5 ring-buffer: Prevent subbuf order change when resizing is disabled
Because ring_buffer_subbuf_order_set() frees buffer pages, we can't
allow it when resizing is disabled. A non-consuming reader is at risk of
use-after-free (rb_advance_iter()).

Return -EBUSY on resize_disabled, matching ring_buffer_resize()
behaviour.

Cc: stable@vger.kernel.org
Fixes: f9b94daa54 ("ring-buffer: Set new size of the ring buffer sub page")
Link: https://patch.msgid.link/20260806211306.3704194-3-vdonnefort@google.com
Reported-by: syzbot+e0cc44465d6bae735679@syzkaller.appspotmail.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:23:45 -04:00
Vincent Donnefort
7c727dfce6 ring-buffer: Prevent resizing of persistent ring buffer
Dynamically resizing a persistent ring buffer is not possible. Disable
the feature.

Cc: stable@vger.kernel.org
Fixes: be68d63a13 ("ring-buffer: Add ring_buffer_alloc_range()")
Link: https://patch.msgid.link/20260806211306.3704194-2-vdonnefort@google.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:23:18 -04:00
Josh Poimboeuf
8b8292d648 ftrace: Fix off-by-one fentry site disable in ftrace_free_mem()
When a module's init text is freed, do_init_module() calls
ftrace_free_mem() with a half-open [start, end) range.  However the
ftrace_cmp_recs() comparator treats the upper bound as inclusive, as all
its other users do, passing 'ip + size - 1'.  So ftrace_free_mem() can
delete a record sitting exactly at 'end', which is outside the freed
range.

For a kernel without CFI or IBT, the first record of a function is at
the function start, which for the first function in a module is also the
base of its text allocation.  As the module allocator packs its regions,
that address is often the 'end' passed by a neighboring module's
do_init_module(), causing the first function's ftrace location to get
disabled, preventing an attempt to livepatch it:

  livepatch: failed to find location for function 'pcspkr_probe'

Convert the exclusive end to the inclusive 'end - 1' the comparator
expects, and return early for an empty range to avoid the subtraction
from underflowing when the init text size is zero.

Cc: stable@vger.kernel.org
Fixes: 42c269c88d ("ftrace: Allow for function tracing to record init functions on boot up")
Link: https://patch.msgid.link/1b5ccfa8095bdb1277f84af1c2c2e2205aca03ae.1785992188.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:22:41 -04:00
Tengda Wu
f27bdc4307 ring-buffer: Use current_context for safe per-CPU buffer swap
The ring_buffer_swap_cpu() function currently checks the per-CPU
committing counter to determine if a buffer is actively being written to
before performing the swap. However, there exists a race window where
this check can be bypassed:

    ring_buffer_lock_reserve
        cpu_buffer = buffer->buffers[cpu];       // cpu_buffer_a
        rb_reserve_next_event
            rb_start_commit // inc committing
            if (unlikely(READ_ONCE(cpu_buffer->buffer) != buffer)) {...}
            __rb_reserve_next
                rb_move_tail
                    rb_end_commit(cpu_buffer);   // dec committing => 0
                    /* interrupt hits here, successfully swaps! */
                    local_inc(&cpu_buffer->committing);

    ring_buffer_unlock_commit
        cpu_buffer = buffer->buffers[cpu];      // cpu_buffer_b
        rb_commit
            rb_end_commit
            RB_WARN_ON(cpu_buffer, !local_read(&cpu_buffer->committing))
                                                // triggers warning

The committing counter can temporarily drop to 0 during a single write
operation (within rb_move_tail), creating a window where swap can
succeed even though the write is still in progress. This leads to
inconsistent buffer state and triggers the RB_WARN_ON in rb_commit().

Replace the committing counter check with current_context checks, which
are set at the entry of ring_buffer_lock_reserve() and remain valid
throughout the entire write operation, providing a reliable indicator of
buffer busy state during swap.

Cc: stable@vger.kernel.org
Fixes: 4239c38fe0 ("ring-buffer: Process commits whenever moving to a new page.")
Link: https://patch.msgid.link/20260803005640.2445666-2-wutengda@huaweicloud.com
Signed-off-by: Tengda Wu <wutengda@huaweicloud.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:22:06 -04:00