linux-rng/drivers/tty/serial, 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 ...

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

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

serial: sc16is7xx: remove useless enable of enhanced features

2025-10-22T10:12:06Z

Commit 43c51bb573aa ("sc16is7xx: make sure device is in suspend once probed") permanently enabled access to the enhanced features in sc16is7xx_probe(), and it is never disabled after that. Therefore, remove re-enable of enhanced features in sc16is7xx_set_baud(). This eliminates a potential useless read + write cycle each time the baud rate is reconfigured. Fixes: 43c51bb573aa ("sc16is7xx: make sure device is in suspend once probed") Cc: stable Signed-off-by: Hugo Villeneuve Link: https://patch.msgid.link/20251006142002.177475-1-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman

serial: 8250_exar: add support for Advantech 2 port card with Device ID 0x0018

2025-10-22T10:11:55Z

The Advantech 2-port serial card with PCI vendor=0x13fe and device=0x0018 has a 'XR17V35X' chip installed on the circuit board. Therefore, this driver can be used instead of theu outdated out-of-tree driver from the manufacturer. Signed-off-by: Florian Eckert Cc: stable Link: https://patch.msgid.link/20250924134115.2667650-1-fe@dev.tdt.de Signed-off-by: Greg Kroah-Hartman

tty: serial: sh-sci: fix RSCI FIFO overrun handling

2025-10-22T10:11:17Z

The receive error handling code is shared between RSCI and all other SCIF port types, but the RSCI overrun_reg is specified as a memory offset, while for other SCIF types it is an enum value used to index into the sci_port_params->regs array, as mentioned above the sci_serial_in() function. For RSCI, the overrun_reg is CSR (0x48), causing the sci_getreg() call inside the sci_handle_fifo_overrun() function to index outside the bounds of the regs array, which currently has a size of 20, as specified by SCI_NR_REGS. Because of this, we end up accessing memory outside of RSCI's rsci_port_params structure, which, when interpreted as a plat_sci_reg, happens to have a non-zero size, causing the following WARN when sci_serial_in() is called, as the accidental size does not match the supported register sizes. The existence of the overrun_reg needs to be checked because SCIx_SH3_SCIF_REGTYPE has overrun_reg set to SCLSR, but SCLSR is not present in the regs array. Avoid calling sci_getreg() for port types which don't use standard register handling. Use the ops->read_reg() and ops->write_reg() functions to properly read and write registers for RSCI, and change the type of the status variable to accommodate the 32-bit CSR register. sci_getreg() and sci_serial_in() are also called with overrun_reg in the sci_mpxed_interrupt() interrupt handler, but that code path is not used for RSCI, as it does not have a muxed interrupt. ------------[ cut here ]------------ Invalid register access WARNING: CPU: 0 PID: 0 at drivers/tty/serial/sh-sci.c:522 sci_serial_in+0x38/0xac Modules linked in: renesas_usbhs at24 rzt2h_adc industrialio_adc sha256 cfg80211 bluetooth ecdh_generic ecc rfkill fuse drm backlight ipv6 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.17.0-rc1+ #30 PREEMPT Hardware name: Renesas RZ/T2H EVK Board based on r9a09g077m44 (DT) pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : sci_serial_in+0x38/0xac lr : sci_serial_in+0x38/0xac sp : ffff800080003e80 x29: ffff800080003e80 x28: ffff800082195b80 x27: 000000000000000d x26: ffff8000821956d0 x25: 0000000000000000 x24: ffff800082195b80 x23: ffff000180e0d800 x22: 0000000000000010 x21: 0000000000000000 x20: 0000000000000010 x19: ffff000180e72000 x18: 000000000000000a x17: ffff8002bcee7000 x16: ffff800080000000 x15: 0720072007200720 x14: 0720072007200720 x13: 0720072007200720 x12: 0720072007200720 x11: 0000000000000058 x10: 0000000000000018 x9 : ffff8000821a6a48 x8 : 0000000000057fa8 x7 : 0000000000000406 x6 : ffff8000821fea48 x5 : ffff00033ef88408 x4 : ffff8002bcee7000 x3 : ffff800082195b80 x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff800082195b80 Call trace: sci_serial_in+0x38/0xac (P) sci_handle_fifo_overrun.isra.0+0x70/0x134 sci_er_interrupt+0x50/0x39c __handle_irq_event_percpu+0x48/0x140 handle_irq_event+0x44/0xb0 handle_fasteoi_irq+0xf4/0x1a0 handle_irq_desc+0x34/0x58 generic_handle_domain_irq+0x1c/0x28 gic_handle_irq+0x4c/0x140 call_on_irq_stack+0x30/0x48 do_interrupt_handler+0x80/0x84 el1_interrupt+0x34/0x68 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x6c/0x70 default_idle_call+0x28/0x58 (P) do_idle+0x1f8/0x250 cpu_startup_entry+0x34/0x3c rest_init+0xd8/0xe0 console_on_rootfs+0x0/0x6c __primary_switched+0x88/0x90 ---[ end trace 0000000000000000 ]--- Cc: stable Fixes: 0666e3fe95ab ("serial: sh-sci: Add support for RZ/T2H SCI") Signed-off-by: Cosmin Tanislav Link: https://patch.msgid.link/20250923154707.1089900-1-cosmin-gabriel.tanislav.xa@renesas.com Signed-off-by: Greg Kroah-Hartman

Merge tag 'tty-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2025-10-07T18:36:01Z

Pull tty driver fix from Greg KH: "Here is a single driver fix for the qcom_geni_serial driver. It has been in my tree for weeks, but missed being sent to you for 6.17-final due to travel on my side. This fixes a reported regression for this driver that prevents 6.17 from working properly on this platform. It has been in linux-next for many weeks with no reported issues" * tag 'tty-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: serial: qcom-geni: Fix blocked task