linux-rng/drivers/tty, branch master

Merge tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T04:18:59Z

Pull objtool updates from Ingo Molnar: - klp-build livepatch module generation (Josh Poimboeuf) Introduce new objtool features and a klp-build script to generate livepatch modules using a source .patch as input. This builds on concepts from the longstanding out-of-tree kpatch project which began in 2012 and has been used for many years to generate livepatch modules for production kernels. However, this is a complete rewrite which incorporates hard-earned lessons from 12+ years of maintaining kpatch. Key improvements compared to kpatch-build: - Integrated with objtool: Leverages objtool's existing control-flow graph analysis to help detect changed functions. - Works on vmlinux.o: Supports late-linked objects, making it compatible with LTO, IBT, and similar. - Simplified code base: ~3k fewer lines of code. - Upstream: No more out-of-tree #ifdef hacks, far less cruft. - Cleaner internals: Vastly simplified logic for symbol/section/reloc inclusion and special section extraction. - Robust __LINE__ macro handling: Avoids false positive binary diffs caused by the __LINE__ macro by introducing a fix-patch-lines script which injects #line directives into the source .patch to preserve the original line numbers at compile time. - Disassemble code with libopcodes instead of running objdump (Alexandre Chartre) - Disassemble support (-d option to objtool) by Alexandre Chartre, which supports the decoding of various Linux kernel code generation specials such as alternatives: 17ef: sched_balance_find_dst_group+0x62f mov 0x34(%r9),%edx 17f3: sched_balance_find_dst_group+0x633 | | X86_FEATURE_POPCNT 17f3: sched_balance_find_dst_group+0x633 | call 0x17f8 <__sw_hweight64> | popcnt %rdi,%rax 17f8: sched_balance_find_dst_group+0x638 cmp %eax,%edx ... jump table alternatives: 1895: sched_use_asym_prio+0x5 test $0x8,%ch 1898: sched_use_asym_prio+0x8 je 0x18a9 189a: sched_use_asym_prio+0xa | | JUMP 189a: sched_use_asym_prio+0xa | jmp 0x18ae | nop2 189c: sched_use_asym_prio+0xc mov $0x1,%eax 18a1: sched_use_asym_prio+0x11 and $0x80,%ecx ... exception table alternatives: native_read_msr: 5b80: native_read_msr+0x0 mov %edi,%ecx 5b82: native_read_msr+0x2 | | EXCEPTION 5b82: native_read_msr+0x2 | rdmsr | resume at 0x5b84 5b84: native_read_msr+0x4 shl $0x20,%rdx .... x86 feature flag decoding (also see the X86_FEATURE_POPCNT example in sched_balance_find_dst_group() above): 2faaf: start_thread_common.constprop.0+0x1f jne 0x2fba4 2fab5: start_thread_common.constprop.0+0x25 | | X86_FEATURE_ALWAYS | X86_BUG_NULL_SEG 2fab5: start_thread_common.constprop.0+0x25 | jmp 0x2faba <.altinstr_aux+0x2f4> | jmp 0x4b0 | nop5 2faba: start_thread_common.constprop.0+0x2a mov $0x2b,%eax ... NOP sequence shortening: 1048e2: snapshot_write_finalize+0xc2 je 0x104917 1048e4: snapshot_write_finalize+0xc4 nop6 1048ea: snapshot_write_finalize+0xca nop11 1048f5: snapshot_write_finalize+0xd5 nop11 104900: snapshot_write_finalize+0xe0 mov %rax,%rcx 104903: snapshot_write_finalize+0xe3 mov 0x10(%rdx),%rax ... and much more. - Function validation tracing support (Alexandre Chartre) - Various -ffunction-sections fixes (Josh Poimboeuf) - Clang AutoFDO (Automated Feedback-Directed Optimizations) support (Josh Poimboeuf) - Misc fixes and cleanups (Borislav Petkov, Chen Ni, Dylan Hatch, Ingo Molnar, John Wang, Josh Poimboeuf, Pankaj Raghav, Peter Zijlstra, Thorsten Blum) * tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits) objtool: Fix segfault on unknown alternatives objtool: Build with disassembly can fail when including bdf.h objtool: Trim trailing NOPs in alternative objtool: Add wide output for disassembly objtool: Compact output for alternatives with one instruction objtool: Improve naming of group alternatives objtool: Add Function to get the name of a CPU feature objtool: Provide access to feature and flags of group alternatives objtool: Fix address references in alternatives objtool: Disassemble jump table alternatives objtool: Disassemble exception table alternatives objtool: Print addresses with alternative instructions objtool: Disassemble group alternatives objtool: Print headers for alternatives objtool: Preserve alternatives order objtool: Add the --disas= action objtool: Do not validate IBT for .return_sites and .call_sites objtool: Improve tracing of alternative instructions objtool: Add functions to better name alternatives objtool: Identify the different types of alternatives ...

Merge tag 'vfs-6.19-rc1.fd_prepare.fs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-02T01:32:07Z

Pull fd prepare updates from Christian Brauner: "This adds the FD_ADD() and FD_PREPARE() primitive. They simplify the common pattern of get_unused_fd_flags() + create file + fd_install() that is used extensively throughout the kernel and currently requires cumbersome cleanup paths. FD_ADD() - For simple cases where a file is installed immediately: fd = FD_ADD(O_CLOEXEC, vfio_device_open_file(device)); if (fd < 0) vfio_device_put_registration(device); return fd; FD_PREPARE() - For cases requiring access to the fd or file, or additional work before publishing: FD_PREPARE(fdf, O_CLOEXEC, sync_file->file); if (fdf.err) { fput(sync_file->file); return fdf.err; } data.fence = fd_prepare_fd(fdf); if (copy_to_user((void __user *)arg, &data, sizeof(data))) return -EFAULT; return fd_publish(fdf); The primitives are centered around struct fd_prepare. FD_PREPARE() encapsulates all allocation and cleanup logic and must be followed by a call to fd_publish() which associates the fd with the file and installs it into the caller's fdtable. If fd_publish() isn't called, both are deallocated automatically. FD_ADD() is a shorthand that does fd_publish() immediately and never exposes the struct to the caller. I've implemented this in a way that it's compatible with the cleanup infrastructure while also being usable separately. IOW, it's centered around struct fd_prepare which is aliased to class_fd_prepare_t and so we can make use of all the basica guard infrastructure" * tag 'vfs-6.19-rc1.fd_prepare.fs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (42 commits) io_uring: convert io_create_mock_file() to FD_PREPARE() file: convert replace_fd() to FD_PREPARE() vfio: convert vfio_group_ioctl_get_device_fd() to FD_ADD() tty: convert ptm_open_peer() to FD_ADD() ntsync: convert ntsync_obj_get_fd() to FD_PREPARE() media: convert media_request_alloc() to FD_PREPARE() hv: convert mshv_ioctl_create_partition() to FD_ADD() gpio: convert linehandle_create() to FD_PREPARE() pseries: port papr_rtas_setup_file_interface() to FD_ADD() pseries: convert papr_platform_dump_create_handle() to FD_ADD() spufs: convert spufs_gang_open() to FD_PREPARE() papr-hvpipe: convert papr_hvpipe_dev_create_handle() to FD_PREPARE() spufs: convert spufs_context_open() to FD_PREPARE() net/socket: convert __sys_accept4_file() to FD_ADD() net/socket: convert sock_map_fd() to FD_ADD() net/kcm: convert kcm_ioctl() to FD_PREPARE() net/handshake: convert handshake_nl_accept_doit() to FD_PREPARE() secretmem: convert memfd_secret() to FD_ADD() memfd: convert memfd_create() to FD_ADD() bpf: convert bpf_token_create() to FD_PREPARE() ...

tty: convert ptm_open_peer() to FD_ADD()

2025-11-28T11:42:36Z

Christian Brauner says: The fix sent in [1] was squashed into this commit. Fixes: https://lore.kernel.org/37ac7af5-584f-4768-a462-4d1071c43eaf@sirena.org.uk [1] Reported-by: Mark Brown [1] Suggested-by: Linus Torvalds [1] Link: https://patch.msgid.link/20251123-work-fd-prepare-v4-42-b6efa1706cfd@kernel.org Signed-off-by: Christian Brauner

serial: 8250: Fix 8250_rsa symbol loop

2025-11-26T12:16:53Z

Depmod fails for a kernel made with: make allnoconfig echo -e "CONFIG_MODULES=y\nCONFIG_SERIAL_8250=m\nCONFIG_SERIAL_8250_EXTENDED=y\nCONFIG_SERIAL_8250_RSA=y" >> .config make olddefconfig ...due to a dependency loop: depmod: ERROR: Cycle detected: 8250 -> 8250_base -> 8250 depmod: ERROR: Found 2 modules in dependency cycles! This is caused by the move of 8250 RSA code from 8250_port.c (in 8250_base.ko) into 8250_rsa.c (in 8250.ko) by the commit 5a128fb475fb ("serial: 8250: move RSA functions to 8250_rsa.c"). The commit b20d6576cdb3 ("serial: 8250: export RSA functions") tried to fix a missing symbol issue with EXPORTs but those then cause this dependency cycle. Break dependency loop by moving 8250_rsa.o from 8250.ko to 8250_base.ko and by passing univ8250_port_base_ops to univ8250_rsa_support() that can make a local copy of it. Reported-by: Stephen Rothwell Reported-by: Alex Davis Fixes: 5a128fb475fb ("serial: 8250: move RSA functions to 8250_rsa.c") Fixes: b20d6576cdb3 ("serial: 8250: export RSA functions") Cc: stable Link: https://lore.kernel.org/all/87frc3sd8d.fsf@posteo.net/ Link: https://lore.kernel.org/all/CADiockCvM6v+d+UoFZpJSMoLAdpy99_h-hJdzUsdfaWGn3W7-g@mail.gmail.com/ Reviewed-by: Andy Shevchenko Reviewed-by: Jiri Slaby Signed-off-by: Ilpo Järvinen Link: https://patch.msgid.link/20251110105043.4062-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman

tty: synclink_gt: Fix namespace collision and startup() section placement with -ffunction-sections

2025-11-21T09:04:10Z

When compiled with -ffunction-sections (e.g., for LTO, livepatch, dead code elimination, AutoFDO, or Propeller), the startup() function gets compiled into the .text.startup section (or in some cases .text.startup.constprop.0 or .text.startup.isra.0). However, the .text.startup and .text.startup.* sections are also used by the compiler for __attribute__((constructor)) code. This naming conflict causes the vmlinux linker script to wrongly place startup() function code in .init.text, which gets freed during boot. Some builds have a mix of objects, both with and without -ffunctions-sections, so it's not possible for the linker script to disambiguate with #ifdef CONFIG_FUNCTION_SECTIONS or similar. This means that "startup" unfortunately needs to be prohibited as a function name. Rename startup() to startup_hw(). For consistency, also rename its shutdown() counterpart to shutdown_hw(). Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Greg Kroah-Hartman Link: https://patch.msgid.link/f0ee750f35c878172cc09916a0724b74e62eadc2.1763669451.git.jpoimboe@kernel.org

tty: amiserial: Fix namespace collision and startup() section placement with -ffunction-sections

2025-11-21T09:04:09Z

When compiled with -ffunction-sections (e.g., for LTO, livepatch, dead code elimination, AutoFDO, or Propeller), the startup() function gets compiled into the .text.startup section (or in some cases .text.startup.constprop.0 or .text.startup.isra.0). However, the .text.startup and .text.startup.* sections are also used by the compiler for __attribute__((constructor)) code. This naming conflict causes the vmlinux linker script to wrongly place startup() function code in .init.text, which gets freed during boot. Some builds have a mix of objects, both with and without -ffunctions-sections, so it's not possible for the linker script to disambiguate with #ifdef CONFIG_FUNCTION_SECTIONS or similar. This means that "startup" unfortunately needs to be prohibited as a function name. Rename startup() to rs_startup(). For consistency, also rename its shutdown() counterpart to rs_shutdown(). Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Greg Kroah-Hartman Link: https://patch.msgid.link/9e56afff5268b0b12b99a8aa9bf244d6ebdcdf47.1763669451.git.jpoimboe@kernel.org

serial: icom: Fix namespace collision and startup() section placement with -ffunction-sections

2025-11-21T09:04:09Z

When compiled with -ffunction-sections (e.g., for LTO, livepatch, dead code elimination, AutoFDO, or Propeller), the startup() function gets compiled into the .text.startup section (or in some cases .text.startup.constprop.0 or .text.startup.isra.0). However, the .text.startup and .text.startup.* sections are also used by the compiler for __attribute__((constructor)) code. This naming conflict causes the vmlinux linker script to wrongly place startup() function code in .init.text, which gets freed during boot. Some builds have a mix of objects, both with and without -ffunctions-sections, so it's not possible for the linker script to disambiguate with #ifdef CONFIG_FUNCTION_SECTIONS or similar. This means that "startup" unfortunately needs to be prohibited as a function name. Rename startup() to icom_startup(). For consistency, also rename its shutdown() counterpart to icom_shutdown(). Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Greg Kroah-Hartman Link: https://patch.msgid.link/1aee9ef69f9d40405676712b34f0c397706e7023.1763669451.git.jpoimboe@kernel.org

serial: amba-pl011: prefer dma_mapping_error() over explicit address checking

2025-10-28T14:26:47Z

Check for returned DMA addresses using specialized dma_mapping_error() helper which is generally recommended for this purpose by Documentation/core-api/dma-api.rst: "In some circumstances dma_map_single(), ... will fail to create a mapping. A driver can check for these errors by testing the returned DMA address with dma_mapping_error()." Found via static analysis and this is similar to commit fa0308134d26 ("ALSA: memalloc: prefer dma_mapping_error() over explicit address checking") Fixes: 58ac1b379979 ("ARM: PL011: Fix DMA support") Cc: stable Signed-off-by: Miaoqian Lin Reviewed-by: Gregory CLEMENT Link: https://patch.msgid.link/20251027092053.87937-1-linmq006@gmail.com Signed-off-by: Greg Kroah-Hartman

serial: 8250_mtk: Enable baud clock and manage in runtime PM

2025-10-22T10:13:54Z

Some MediaTek SoCs got a gated UART baud clock, which currently gets disabled as the clk subsystem believes it would be unused. This results in the uart freezing right after "clk: Disabling unused clocks" on those platforms. Request the baud clock to be prepared and enabled during probe, and to restore run-time power management capabilities to what it was before commit e32a83c70cf9 ("serial: 8250-mtk: modify mtk uart power and clock management") disable and unprepare the baud clock when suspending the UART, prepare and enable it again when resuming it. Fixes: e32a83c70cf9 ("serial: 8250-mtk: modify mtk uart power and clock management") Fixes: b6c7ff2693ddc ("serial: 8250_mtk: Simplify clock sequencing and runtime PM") Cc: stable Reviewed-by: AngeloGioacchino Del Regno Signed-off-by: Daniel Golle Link: https://patch.msgid.link/de5197ccc31e1dab0965cabcc11ca92e67246cf6.1758058441.git.daniel@makrotopia.org Signed-off-by: Greg Kroah-Hartman

serial: 8250_dw: handle reset control deassert error

2025-10-22T10:13:12Z

Check the return value of reset_control_deassert() in the probe function to prevent continuing probe when reset deassertion fails. Previously, reset_control_deassert() was called without checking its return value, which could lead to probe continuing even when the device reset wasn't properly deasserted. The fix checks the return value and returns an error with dev_err_probe() if reset deassertion fails, providing better error handling and diagnostics. Fixes: acbdad8dd1ab ("serial: 8250_dw: simplify optional reset handling") Cc: stable Signed-off-by: Artem Shimko Link: https://patch.msgid.link/20251019095131.252848-1-a.shimko.dev@gmail.com Signed-off-by: Greg Kroah-Hartman