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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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+.. SPDX-License-Identifier: GPL-2.0
+
+Undefined Behavior Sanitizer - UBSAN
+====================================
+
+UBSAN is a runtime undefined behaviour checker.
+
+UBSAN uses compile-time instrumentation to catch undefined behavior (UB).
+Compiler inserts code that perform certain kinds of checks before operations
+that may cause UB. If check fails (i.e. UB detected) __ubsan_handle_*
+function called to print error message.
+
+GCC has that feature since 4.9.x [1_] (see ``-fsanitize=undefined`` option and
+its suboptions). GCC 5.x has more checkers implemented [2_].
+
+Report example
+--------------
+
+::
+
+ ================================================================================
+ UBSAN: Undefined behaviour in ../include/linux/bitops.h:110:33
+ shift exponent 32 is to large for 32-bit type 'unsigned int'
+ CPU: 0 PID: 0 Comm: swapper Not tainted 4.4.0-rc1+ #26
+ 0000000000000000 ffffffff82403cc8 ffffffff815e6cd6 0000000000000001
+ ffffffff82403cf8 ffffffff82403ce0 ffffffff8163a5ed 0000000000000020
+ ffffffff82403d78 ffffffff8163ac2b ffffffff815f0001 0000000000000002
+ Call Trace:
+ [<ffffffff815e6cd6>] dump_stack+0x45/0x5f
+ [<ffffffff8163a5ed>] ubsan_epilogue+0xd/0x40
+ [<ffffffff8163ac2b>] __ubsan_handle_shift_out_of_bounds+0xeb/0x130
+ [<ffffffff815f0001>] ? radix_tree_gang_lookup_slot+0x51/0x150
+ [<ffffffff8173c586>] _mix_pool_bytes+0x1e6/0x480
+ [<ffffffff83105653>] ? dmi_walk_early+0x48/0x5c
+ [<ffffffff8173c881>] add_device_randomness+0x61/0x130
+ [<ffffffff83105b35>] ? dmi_save_one_device+0xaa/0xaa
+ [<ffffffff83105653>] dmi_walk_early+0x48/0x5c
+ [<ffffffff831066ae>] dmi_scan_machine+0x278/0x4b4
+ [<ffffffff8111d58a>] ? vprintk_default+0x1a/0x20
+ [<ffffffff830ad120>] ? early_idt_handler_array+0x120/0x120
+ [<ffffffff830b2240>] setup_arch+0x405/0xc2c
+ [<ffffffff830ad120>] ? early_idt_handler_array+0x120/0x120
+ [<ffffffff830ae053>] start_kernel+0x83/0x49a
+ [<ffffffff830ad120>] ? early_idt_handler_array+0x120/0x120
+ [<ffffffff830ad386>] x86_64_start_reservations+0x2a/0x2c
+ [<ffffffff830ad4f3>] x86_64_start_kernel+0x16b/0x17a
+ ================================================================================
+
+Usage
+-----
+
+To enable UBSAN, configure the kernel with::
+
+ CONFIG_UBSAN=y
+
+To exclude files from being instrumented use::
+
+ UBSAN_SANITIZE_main.o := n
+
+and to exclude all targets in one directory use::
+
+ UBSAN_SANITIZE := n
+
+When disabled for all targets, specific files can be enabled using::
+
+ UBSAN_SANITIZE_main.o := y
+
+Detection of unaligned accesses controlled through the separate option -
+CONFIG_UBSAN_ALIGNMENT. It's off by default on architectures that support
+unaligned accesses (CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y). One could
+still enable it in config, just note that it will produce a lot of UBSAN
+reports.
+
+References
+----------
+
+.. _1: https://gcc.gnu.org/onlinedocs/gcc-4.9.0/gcc/Debugging-Options.html
+.. _2: https://gcc.gnu.org/onlinedocs/gcc/Debugging-Options.html
+.. _3: https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html