From 932d8476399f622aa0767a4a0a9e78e5341dc0e1 Mon Sep 17 00:00:00 2001 From: Yuntao Wang Date: Wed, 15 May 2024 21:45:54 +0800 Subject: cpu/hotplug: Fix dynstate assignment in __cpuhp_setup_state_cpuslocked() Commit 4205e4786d0b ("cpu/hotplug: Provide dynamic range for prepare stage") added a dynamic range for the prepare states, but did not handle the assignment of the dynstate variable in __cpuhp_setup_state_cpuslocked(). This causes the corresponding startup callback not to be invoked when calling __cpuhp_setup_state_cpuslocked() with the CPUHP_BP_PREPARE_DYN parameter, even though it should be. Currently, the users of __cpuhp_setup_state_cpuslocked(), for one reason or another, have not triggered this bug. Fixes: 4205e4786d0b ("cpu/hotplug: Provide dynamic range for prepare stage") Signed-off-by: Yuntao Wang Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240515134554.427071-1-ytcoode@gmail.com --- kernel/cpu.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/cpu.c b/kernel/cpu.c index 563877d6c28b..74cfdb66a9bd 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -2446,7 +2446,7 @@ EXPORT_SYMBOL_GPL(__cpuhp_state_add_instance); * The caller needs to hold cpus read locked while calling this function. * Return: * On success: - * Positive state number if @state is CPUHP_AP_ONLINE_DYN; + * Positive state number if @state is CPUHP_AP_ONLINE_DYN or CPUHP_BP_PREPARE_DYN; * 0 for all other states * On failure: proper (negative) error code */ @@ -2469,7 +2469,7 @@ int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, ret = cpuhp_store_callbacks(state, name, startup, teardown, multi_instance); - dynstate = state == CPUHP_AP_ONLINE_DYN; + dynstate = state == CPUHP_AP_ONLINE_DYN || state == CPUHP_BP_PREPARE_DYN; if (ret > 0 && dynstate) { state = ret; ret = 0; @@ -2500,8 +2500,8 @@ int __cpuhp_setup_state_cpuslocked(enum cpuhp_state state, out: mutex_unlock(&cpuhp_state_mutex); /* - * If the requested state is CPUHP_AP_ONLINE_DYN, return the - * dynamically allocated state in case of success. + * If the requested state is CPUHP_AP_ONLINE_DYN or CPUHP_BP_PREPARE_DYN, + * return the dynamically allocated state in case of success. */ if (!ret && dynstate) return state; -- cgit v1.2.3 From 6ef8eb5125722c241fd60d7b0c872d5c2e5dd4ca Mon Sep 17 00:00:00 2001 From: Huacai Chen Date: Tue, 18 Jun 2024 16:13:36 +0800 Subject: cpu: Fix broken cmdline "nosmp" and "maxcpus=0" After the rework of "Parallel CPU bringup", the cmdline "nosmp" and "maxcpus=0" parameters are not working anymore. These parameters set setup_max_cpus to zero and that's handed to bringup_nonboot_cpus(). The code there does a decrement before checking for zero, which brings it into the negative space and brings up all CPUs. Add a zero check at the beginning of the function to prevent this. [ tglx: Massaged change log ] Fixes: 18415f33e2ac4ab382 ("cpu/hotplug: Allow "parallel" bringup up to CPUHP_BP_KICK_AP_STATE") Fixes: 06c6796e0304234da6 ("cpu/hotplug: Fix off by one in cpuhp_bringup_mask()") Signed-off-by: Huacai Chen Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240618081336.3996825-1-chenhuacai@loongson.cn --- kernel/cpu.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel') diff --git a/kernel/cpu.c b/kernel/cpu.c index 74cfdb66a9bd..3d2bf1d50a0c 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1859,6 +1859,9 @@ static inline bool cpuhp_bringup_cpus_parallel(unsigned int ncpus) { return fals void __init bringup_nonboot_cpus(unsigned int max_cpus) { + if (!max_cpus) + return; + /* Try parallel bringup optimization if enabled */ if (cpuhp_bringup_cpus_parallel(max_cpus)) return; -- cgit v1.2.3 From deb091cb05a2b8555e15fcc2df5a0dcd9d06fea0 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 25 Jun 2024 07:58:03 +0200 Subject: Revert "printk: Flag register_console() if console is set on command line" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This reverts commit b73c9cbe4f1fc02645228aa575998dd54067f8ef. Let's roll back all of the serial core and printk console changes that went into 6.10-rc1 as there still are problems with them that need to be sorted out. Link: https://lore.kernel.org/r/ZnpRozsdw6zbjqze@tlindgre-MOBL1 Reported-by: Petr Mladek Reported-by: Tony Lindgren Cc: Jiri Slaby Cc: John Ogness Cc: Sergey Senozhatsky Cc: Andy Shevchenko Cc: Ilpo Järvinen Signed-off-by: Greg Kroah-Hartman --- kernel/printk/printk.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 420fd310129d..e6e6a47acec8 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2504,9 +2504,6 @@ static int __init console_setup(char *str) if (console_opt_save(str, brl_options)) return 1; - /* Flag register_console() to not call try_enable_default_console() */ - console_set_on_cmdline = 1; - /* Don't attempt to parse a DEVNAME:0.0 style console */ if (strchr(str, ':')) return 1; @@ -3522,7 +3519,7 @@ void register_console(struct console *newcon) * Note that a console with tty binding will have CON_CONSDEV * flag set and will be first in the list. */ - if (preferred_console < 0 && !console_set_on_cmdline) { + if (preferred_console < 0) { if (hlist_empty(&console_list) || !console_first()->device || console_first()->flags & CON_BOOT) { try_enable_default_console(newcon); -- cgit v1.2.3 From 64f9f010c6177dd4f33e5023d2eab9af4af291e9 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 25 Jun 2024 07:58:07 +0200 Subject: Revert "printk: Don't try to parse DEVNAME:0.0 console options" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This reverts commit 8a831c584e6e80cf68f79893dc395c16cdf47dc8. Let's roll back all of the serial core and printk console changes that went into 6.10-rc1 as there still are problems with them that need to be sorted out. Link: https://lore.kernel.org/r/ZnpRozsdw6zbjqze@tlindgre-MOBL1 Reported-by: Petr Mladek Reported-by: Tony Lindgren Cc: Jiri Slaby Cc: John Ogness Cc: Sergey Senozhatsky Cc: Andy Shevchenko Cc: Ilpo Järvinen Signed-off-by: Greg Kroah-Hartman --- kernel/printk/printk.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'kernel') diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index e6e6a47acec8..b582404cd29d 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -2504,10 +2504,6 @@ static int __init console_setup(char *str) if (console_opt_save(str, brl_options)) return 1; - /* Don't attempt to parse a DEVNAME:0.0 style console */ - if (strchr(str, ':')) - return 1; - /* * Decode str into name, index, options. */ -- cgit v1.2.3 From cc8d5a2f09a54405321769abfd6ec3395482336a Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 25 Jun 2024 07:58:10 +0200 Subject: Revert "printk: Save console options for add_preferred_console_match()" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This reverts commit f03e8c1060f86c23eb49bafee99d9fcbd1c1bd77. Let's roll back all of the serial core and printk console changes that went into 6.10-rc1 as there still are problems with them that need to be sorted out. Link: https://lore.kernel.org/r/ZnpRozsdw6zbjqze@tlindgre-MOBL1 Reported-by: Petr Mladek Reported-by: Tony Lindgren Cc: Jiri Slaby Cc: John Ogness Cc: Sergey Senozhatsky Cc: Andy Shevchenko Cc: Ilpo Järvinen Signed-off-by: Greg Kroah-Hartman --- kernel/printk/Makefile | 2 +- kernel/printk/conopt.c | 146 ---------------------------------------- kernel/printk/console_cmdline.h | 6 -- kernel/printk/printk.c | 14 +--- 4 files changed, 4 insertions(+), 164 deletions(-) delete mode 100644 kernel/printk/conopt.c (limited to 'kernel') diff --git a/kernel/printk/Makefile b/kernel/printk/Makefile index 040fe7d1eda2..39a2b61c7232 100644 --- a/kernel/printk/Makefile +++ b/kernel/printk/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only -obj-y = printk.o conopt.o +obj-y = printk.o obj-$(CONFIG_PRINTK) += printk_safe.o nbcon.o obj-$(CONFIG_A11Y_BRAILLE_CONSOLE) += braille.o obj-$(CONFIG_PRINTK_INDEX) += index.o diff --git a/kernel/printk/conopt.c b/kernel/printk/conopt.c deleted file mode 100644 index 9d507bac3657..000000000000 --- a/kernel/printk/conopt.c +++ /dev/null @@ -1,146 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Kernel command line console options for hardware based addressing - * - * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/ - * Author: Tony Lindgren - */ - -#include -#include -#include -#include - -#include - -#include "console_cmdline.h" - -/* - * Allow longer DEVNAME:0.0 style console naming such as abcd0000.serial:0.0 - * in addition to the legacy ttyS0 style naming. - */ -#define CONSOLE_NAME_MAX 32 - -#define CONSOLE_OPT_MAX 16 -#define CONSOLE_BRL_OPT_MAX 16 - -struct console_option { - char name[CONSOLE_NAME_MAX]; - char opt[CONSOLE_OPT_MAX]; - char brl_opt[CONSOLE_BRL_OPT_MAX]; - u8 has_brl_opt:1; -}; - -/* Updated only at console_setup() time, no locking needed */ -static struct console_option conopt[MAX_CMDLINECONSOLES]; - -/** - * console_opt_save - Saves kernel command line console option for driver use - * @str: Kernel command line console name and option - * @brl_opt: Braille console options - * - * Saves a kernel command line console option for driver subsystems to use for - * adding a preferred console during init. Called from console_setup() only. - * - * Return: 0 on success, negative error code on failure. - */ -int __init console_opt_save(const char *str, const char *brl_opt) -{ - struct console_option *con; - size_t namelen, optlen; - const char *opt; - int i; - - namelen = strcspn(str, ","); - if (namelen == 0 || namelen >= CONSOLE_NAME_MAX) - return -EINVAL; - - opt = str + namelen; - if (*opt == ',') - opt++; - - optlen = strlen(opt); - if (optlen >= CONSOLE_OPT_MAX) - return -EINVAL; - - for (i = 0; i < MAX_CMDLINECONSOLES; i++) { - con = &conopt[i]; - - if (con->name[0]) { - if (!strncmp(str, con->name, namelen)) - return 0; - continue; - } - - /* - * The name isn't terminated, only opt is. Empty opt is fine, - * but brl_opt can be either empty or NULL. For more info, see - * _braille_console_setup(). - */ - strscpy(con->name, str, namelen + 1); - strscpy(con->opt, opt, CONSOLE_OPT_MAX); - if (brl_opt) { - strscpy(con->brl_opt, brl_opt, CONSOLE_BRL_OPT_MAX); - con->has_brl_opt = 1; - } - - return 0; - } - - return -ENOMEM; -} - -static struct console_option *console_opt_find(const char *name) -{ - struct console_option *con; - int i; - - for (i = 0; i < MAX_CMDLINECONSOLES; i++) { - con = &conopt[i]; - if (!strcmp(name, con->name)) - return con; - } - - return NULL; -} - -/** - * add_preferred_console_match - Adds a preferred console if a match is found - * @match: Expected console on kernel command line, such as console=DEVNAME:0.0 - * @name: Name of the console character device to add such as ttyS - * @idx: Index for the console - * - * Allows driver subsystems to add a console after translating the command - * line name to the character device name used for the console. Options are - * added automatically based on the kernel command line. Duplicate preferred - * consoles are ignored by __add_preferred_console(). - * - * Return: 0 on success, negative error code on failure. - */ -int add_preferred_console_match(const char *match, const char *name, - const short idx) -{ - struct console_option *con; - char *brl_opt = NULL; - - if (!match || !strlen(match) || !name || !strlen(name) || - idx < 0) - return -EINVAL; - - con = console_opt_find(match); - if (!con) - return -ENOENT; - - /* - * See __add_preferred_console(). It checks for NULL brl_options to set - * the preferred_console flag. Empty brl_opt instead of NULL leads into - * the preferred_console flag not set, and CON_CONSDEV not being set, - * and the boot console won't get disabled at the end of console_setup(). - */ - if (con->has_brl_opt) - brl_opt = con->brl_opt; - - console_opt_add_preferred_console(name, idx, con->opt, brl_opt); - - return 0; -} diff --git a/kernel/printk/console_cmdline.h b/kernel/printk/console_cmdline.h index a125e0235589..3ca74ad391d6 100644 --- a/kernel/printk/console_cmdline.h +++ b/kernel/printk/console_cmdline.h @@ -2,12 +2,6 @@ #ifndef _CONSOLE_CMDLINE_H #define _CONSOLE_CMDLINE_H -#define MAX_CMDLINECONSOLES 8 - -int console_opt_save(const char *str, const char *brl_opt); -int console_opt_add_preferred_console(const char *name, const short idx, - char *options, char *brl_options); - struct console_cmdline { char name[16]; /* Name of the driver */ diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index b582404cd29d..dddb15f48d59 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -383,6 +383,9 @@ static int console_locked; /* * Array of consoles built from command line options (console=) */ + +#define MAX_CMDLINECONSOLES 8 + static struct console_cmdline console_cmdline[MAX_CMDLINECONSOLES]; static int preferred_console = -1; @@ -2500,10 +2503,6 @@ static int __init console_setup(char *str) if (_braille_console_setup(&str, &brl_options)) return 1; - /* Save the console for driver subsystem use */ - if (console_opt_save(str, brl_options)) - return 1; - /* * Decode str into name, index, options. */ @@ -2534,13 +2533,6 @@ static int __init console_setup(char *str) } __setup("console=", console_setup); -/* Only called from add_preferred_console_match() */ -int console_opt_add_preferred_console(const char *name, const short idx, - char *options, char *brl_options) -{ - return __add_preferred_console(name, idx, options, brl_options, true); -} - /** * add_preferred_console - add a device to the list of preferred consoles. * @name: device name -- cgit v1.2.3 From d3882564a77c21eb746ba5364f3fa89b88de3d61 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 20 Jun 2024 14:16:37 +0200 Subject: syscalls: fix compat_sys_io_pgetevents_time64 usage Using sys_io_pgetevents() as the entry point for compat mode tasks works almost correctly, but misses the sign extension for the min_nr and nr arguments. This was addressed on parisc by switching to compat_sys_io_pgetevents_time64() in commit 6431e92fc827 ("parisc: io_pgetevents_time64() needs compat syscall in 32-bit compat mode"), as well as by using more sophisticated system call wrappers on x86 and s390. However, arm64, mips, powerpc, sparc and riscv still have the same bug. Change all of them over to use compat_sys_io_pgetevents_time64() like parisc already does. This was clearly the intention when the function was originally added, but it got hooked up incorrectly in the tables. Cc: stable@vger.kernel.org Fixes: 48166e6ea47d ("y2038: add 64-bit time_t syscalls to all 32-bit architectures") Acked-by: Heiko Carstens # s390 Signed-off-by: Arnd Bergmann --- kernel/sys_ni.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index d7eee421d4bc..b696b85ac63e 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -46,8 +46,8 @@ COND_SYSCALL(io_getevents_time32); COND_SYSCALL(io_getevents); COND_SYSCALL(io_pgetevents_time32); COND_SYSCALL(io_pgetevents); -COND_SYSCALL_COMPAT(io_pgetevents_time32); COND_SYSCALL_COMPAT(io_pgetevents); +COND_SYSCALL_COMPAT(io_pgetevents_time64); COND_SYSCALL(io_uring_setup); COND_SYSCALL(io_uring_enter); COND_SYSCALL(io_uring_register); -- cgit v1.2.3 From 5a830bbce3af16833fe0092dec47b6dd30279825 Mon Sep 17 00:00:00 2001 From: Phil Chang Date: Mon, 10 Jun 2024 21:31:36 +0800 Subject: hrtimer: Prevent queuing of hrtimer without a function callback The hrtimer function callback must not be NULL. It has to be specified by the call side but it is not validated by the hrtimer code. When a hrtimer is queued without a function callback, the kernel crashes with a null pointer dereference when trying to execute the callback in __run_hrtimer(). Introduce a validation before queuing the hrtimer in hrtimer_start_range_ns(). [anna-maria: Rephrase commit message] Signed-off-by: Phil Chang Signed-off-by: Anna-Maria Behnsen Signed-off-by: Thomas Gleixner Reviewed-by: Anna-Maria Behnsen --- kernel/time/hrtimer.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel') diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 492c14aac642..b8ee320208d4 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1285,6 +1285,8 @@ void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim, struct hrtimer_clock_base *base; unsigned long flags; + if (WARN_ON_ONCE(!timer->function)) + return; /* * Check whether the HRTIMER_MODE_SOFT bit and hrtimer.is_soft * match on CONFIG_PREEMPT_RT = n. With PREEMPT_RT check the hard -- cgit v1.2.3 From 7e1f4eb9a60d40dd17a97d9b76818682a024a127 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 4 Apr 2024 12:04:54 +0200 Subject: kallsyms: rework symbol lookup return codes Building with W=1 in some configurations produces a false positive warning for kallsyms: kernel/kallsyms.c: In function '__sprint_symbol.isra': kernel/kallsyms.c:503:17: error: 'strcpy' source argument is the same as destination [-Werror=restrict] 503 | strcpy(buffer, name); | ^~~~~~~~~~~~~~~~~~~~ This originally showed up while building with -O3, but later started happening in other configurations as well, depending on inlining decisions. The underlying issue is that the local 'name' variable is always initialized to the be the same as 'buffer' in the called functions that fill the buffer, which gcc notices while inlining, though it could see that the address check always skips the copy. The calling conventions here are rather unusual, as all of the internal lookup functions (bpf_address_lookup, ftrace_mod_address_lookup, ftrace_func_address_lookup, module_address_lookup and kallsyms_lookup_buildid) already use the provided buffer and either return the address of that buffer to indicate success, or NULL for failure, but the callers are written to also expect an arbitrary other buffer to be returned. Rework the calling conventions to return the length of the filled buffer instead of its address, which is simpler and easier to follow as well as avoiding the warning. Leave only the kallsyms_lookup() calling conventions unchanged, since that is called from 16 different functions and adapting this would be a much bigger change. Link: https://lore.kernel.org/lkml/20200107214042.855757-1-arnd@arndb.de/ Link: https://lore.kernel.org/lkml/20240326130647.7bfb1d92@gandalf.local.home/ Tested-by: Geert Uytterhoeven Reviewed-by: Luis Chamberlain Acked-by: Steven Rostedt (Google) Signed-off-by: Arnd Bergmann --- kernel/bpf/core.c | 7 +++---- kernel/kallsyms.c | 23 ++++++++++++----------- kernel/module/kallsyms.c | 25 ++++++++++++------------- kernel/trace/ftrace.c | 13 +++++-------- 4 files changed, 32 insertions(+), 36 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 1a6c3faa6e4a..695a0fb2cd4d 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -736,11 +736,11 @@ static struct bpf_ksym *bpf_ksym_find(unsigned long addr) return n ? container_of(n, struct bpf_ksym, tnode) : NULL; } -const char *__bpf_address_lookup(unsigned long addr, unsigned long *size, +int __bpf_address_lookup(unsigned long addr, unsigned long *size, unsigned long *off, char *sym) { struct bpf_ksym *ksym; - char *ret = NULL; + int ret = 0; rcu_read_lock(); ksym = bpf_ksym_find(addr); @@ -748,9 +748,8 @@ const char *__bpf_address_lookup(unsigned long addr, unsigned long *size, unsigned long symbol_start = ksym->start; unsigned long symbol_end = ksym->end; - strscpy(sym, ksym->name, KSYM_NAME_LEN); + ret = strscpy(sym, ksym->name, KSYM_NAME_LEN); - ret = sym; if (size) *size = symbol_end - symbol_start; if (off) diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 22ea19a36e6e..98b9622d372e 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -388,12 +388,12 @@ int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize, !!__bpf_address_lookup(addr, symbolsize, offset, namebuf); } -static const char *kallsyms_lookup_buildid(unsigned long addr, +static int kallsyms_lookup_buildid(unsigned long addr, unsigned long *symbolsize, unsigned long *offset, char **modname, const unsigned char **modbuildid, char *namebuf) { - const char *ret; + int ret; namebuf[KSYM_NAME_LEN - 1] = 0; namebuf[0] = 0; @@ -410,7 +410,7 @@ static const char *kallsyms_lookup_buildid(unsigned long addr, if (modbuildid) *modbuildid = NULL; - ret = namebuf; + ret = strlen(namebuf); goto found; } @@ -442,8 +442,13 @@ const char *kallsyms_lookup(unsigned long addr, unsigned long *offset, char **modname, char *namebuf) { - return kallsyms_lookup_buildid(addr, symbolsize, offset, modname, - NULL, namebuf); + int ret = kallsyms_lookup_buildid(addr, symbolsize, offset, modname, + NULL, namebuf); + + if (!ret) + return NULL; + + return namebuf; } int lookup_symbol_name(unsigned long addr, char *symname) @@ -478,19 +483,15 @@ static int __sprint_symbol(char *buffer, unsigned long address, { char *modname; const unsigned char *buildid; - const char *name; unsigned long offset, size; int len; address += symbol_offset; - name = kallsyms_lookup_buildid(address, &size, &offset, &modname, &buildid, + len = kallsyms_lookup_buildid(address, &size, &offset, &modname, &buildid, buffer); - if (!name) + if (!len) return sprintf(buffer, "0x%lx", address - symbol_offset); - if (name != buffer) - strcpy(buffer, name); - len = strlen(buffer); offset -= symbol_offset; if (add_offset) diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c index 62fb57bb9f16..bf65e0c3c86f 100644 --- a/kernel/module/kallsyms.c +++ b/kernel/module/kallsyms.c @@ -321,14 +321,15 @@ void * __weak dereference_module_function_descriptor(struct module *mod, * For kallsyms to ask for address resolution. NULL means not found. Careful * not to lock to avoid deadlock on oopses, simply disable preemption. */ -const char *module_address_lookup(unsigned long addr, - unsigned long *size, - unsigned long *offset, - char **modname, - const unsigned char **modbuildid, - char *namebuf) +int module_address_lookup(unsigned long addr, + unsigned long *size, + unsigned long *offset, + char **modname, + const unsigned char **modbuildid, + char *namebuf) { - const char *ret = NULL; + const char *sym; + int ret = 0; struct module *mod; preempt_disable(); @@ -344,12 +345,10 @@ const char *module_address_lookup(unsigned long addr, #endif } - ret = find_kallsyms_symbol(mod, addr, size, offset); - } - /* Make a copy in here where it's safe */ - if (ret) { - strscpy(namebuf, ret, KSYM_NAME_LEN); - ret = namebuf; + sym = find_kallsyms_symbol(mod, addr, size, offset); + + if (sym) + ret = strscpy(namebuf, sym, KSYM_NAME_LEN); } preempt_enable(); diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 65208d3b5ed9..eacab4020508 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6969,7 +6969,7 @@ allocate_ftrace_mod_map(struct module *mod, return mod_map; } -static const char * +static int ftrace_func_address_lookup(struct ftrace_mod_map *mod_map, unsigned long addr, unsigned long *size, unsigned long *off, char *sym) @@ -6990,21 +6990,18 @@ ftrace_func_address_lookup(struct ftrace_mod_map *mod_map, *size = found_func->size; if (off) *off = addr - found_func->ip; - if (sym) - strscpy(sym, found_func->name, KSYM_NAME_LEN); - - return found_func->name; + return strscpy(sym, found_func->name, KSYM_NAME_LEN); } - return NULL; + return 0; } -const char * +int ftrace_mod_address_lookup(unsigned long addr, unsigned long *size, unsigned long *off, char **modname, char *sym) { struct ftrace_mod_map *mod_map; - const char *ret = NULL; + int ret = 0; /* mod_map is freed via call_rcu() */ preempt_disable(); -- cgit v1.2.3 From cf3f9a593dab87a032d2b6a6fb205e7f3de4f0a1 Mon Sep 17 00:00:00 2001 From: Jinliang Zheng Date: Thu, 20 Jun 2024 20:21:24 +0800 Subject: mm: optimize the redundant loop of mm_update_owner_next() When mm_update_owner_next() is racing with swapoff (try_to_unuse()) or /proc or ptrace or page migration (get_task_mm()), it is impossible to find an appropriate task_struct in the loop whose mm_struct is the same as the target mm_struct. If the above race condition is combined with the stress-ng-zombie and stress-ng-dup tests, such a long loop can easily cause a Hard Lockup in write_lock_irq() for tasklist_lock. Recognize this situation in advance and exit early. Link: https://lkml.kernel.org/r/20240620122123.3877432-1-alexjlzheng@tencent.com Signed-off-by: Jinliang Zheng Acked-by: Michal Hocko Cc: Christian Brauner Cc: Jens Axboe Cc: Mateusz Guzik Cc: Matthew Wilcox (Oracle) Cc: Oleg Nesterov Cc: Tycho Andersen Cc: Signed-off-by: Andrew Morton --- kernel/exit.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel') diff --git a/kernel/exit.c b/kernel/exit.c index f95a2c1338a8..81fcee45d630 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -484,6 +484,8 @@ retry: * Search through everything else, we should not get here often. */ for_each_process(g) { + if (atomic_read(&mm->mm_users) <= 1) + break; if (g->flags & PF_KTHREAD) continue; for_each_thread(g, c) { -- cgit v1.2.3