kernel/linux.git/include/linux, branch v4.19.283

printk: declare printk_deferred_{enter,safe}() in include/linux/printk.h

2023-05-17T09:13:28+00:00

commit 85e3e7fbbb720b9897fba9a99659e31cbd1c082e upstream. [This patch implements subset of original commit 85e3e7fbbb72 ("printk: remove NMI tracking") where commit 1007843a9190 ("mm/page_alloc: fix potential deadlock on zonelist_update_seq seqlock") depends on, for commit 3d36424b3b58 ("mm/page_alloc: fix race condition between build_all_zonelists and page allocation") was backported to stable.] All NMI contexts are handled the same as the safe context: store the message and defer printing. There is no need to have special NMI context tracking for this. Using in_nmi() is enough. There are several parts of the kernel that are manually calling into the printk NMI context tracking in order to cause general printk deferred printing: arch/arm/kernel/smp.c arch/powerpc/kexec/crash.c kernel/trace/trace.c For arm/kernel/smp.c and powerpc/kexec/crash.c, provide a new function pair printk_deferred_enter/exit that explicitly achieves the same objective. For ftrace, remove the printk context manipulation completely. It was added in commit 03fc7f9c99c1 ("printk/nmi: Prevent deadlock when accessing the main log buffer in NMI"). The purpose was to enforce storing messages directly into the ring buffer even in NMI context. It really should have only modified the behavior in NMI context. There is no need for a special behavior any longer. All messages are always stored directly now. The console deferring is handled transparently in vprintk(). Signed-off-by: John Ogness [pmladek@suse.com: Remove special handling in ftrace.c completely. Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20210715193359.25946-5-john.ogness@linutronix.de [penguin-kernel: Copy only printk_deferred_{enter,safe}() definition ] Signed-off-by: Tetsuo Handa Signed-off-by: Greg Kroah-Hartman

tty: Prevent writing chars during tcsetattr TCSADRAIN/FLUSH

2023-05-17T09:13:27+00:00

If userspace races tcsetattr() with a write, the drained condition might not be guaranteed by the kernel. There is a race window after checking Tx is empty before tty_set_termios() takes termios_rwsem for write. During that race window, more characters can be queued by a racing writer. Any ongoing transmission might produce garbage during HW's ->set_termios() call. The intent of TCSADRAIN/FLUSH seems to be preventing such a character corruption. If those flags are set, take tty's write lock to stop any writer before performing the lower layer Tx empty check and wait for the pending characters to be sent (if any). The initial wait for all-writers-done must be placed outside of tty's write lock to avoid deadlock which makes it impossible to use tty_wait_until_sent(). The write lock is retried if a racing write is detected. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20230317113318.31327-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman (cherry picked from commit 094fb49a2d0d6827c86d2e0840873e6db0c491d2) Signed-off-by: Ilpo Järvinen Signed-off-by: Greg Kroah-Hartman

ipmi: Fix how the lower layers are told to watch for messages

2023-05-17T09:13:22+00:00

[ Upstream commit c65ea996595005be470fbfa16711deba414fd33b ] The IPMI driver has a mechanism to tell the lower layers it needs to watch for messages, commands, and watchdogs (so it doesn't needlessly poll). However, it needed some extensions, it needed a way to tell what is being waited for so it could set the timeout appropriately. The update to the lower layer was also being done once a second at best because it was done in the main timeout handler. However, if a command is sent and a response message is coming back, it needed to be started immediately. So modify the code to update immediately if it needs to be enabled. Disable is still lazy. Signed-off-by: Corey Minyard Tested-by: Kamlakant Patel Stable-dep-of: 6d2555cde291 ("ipmi: fix SSIF not responding under certain cond.") Signed-off-by: Sasha Levin

tick/nohz: Fix cpu_is_hotpluggable() by checking with nohz subsystem

2023-05-17T09:13:22+00:00

[ Upstream commit 58d7668242647e661a20efe065519abd6454287e ] For CONFIG_NO_HZ_FULL systems, the tick_do_timer_cpu cannot be offlined. However, cpu_is_hotpluggable() still returns true for those CPUs. This causes torture tests that do offlining to end up trying to offline this CPU causing test failures. Such failure happens on all architectures. Fix the repeated error messages thrown by this (even if the hotplug errors are harmless) by asking the opinion of the nohz subsystem on whether the CPU can be hotplugged. [ Apply Frederic Weisbecker feedback on refactoring tick_nohz_cpu_down(). ] For drivers/base/ portion: Acked-by: Greg Kroah-Hartman Acked-by: Frederic Weisbecker Cc: Frederic Weisbecker Cc: "Paul E. McKenney" Cc: Zhouyi Zhou Cc: Will Deacon Cc: Marc Zyngier Cc: rcu Cc: stable@vger.kernel.org Fixes: 2987557f52b9 ("driver-core/cpu: Expose hotpluggability to the rest of the kernel") Signed-off-by: Paul E. McKenney Signed-off-by: Joel Fernandes (Google) Signed-off-by: Sasha Levin

nohz: Add TICK_DEP_BIT_RCU

2023-05-17T09:13:22+00:00

[ Upstream commit 01b4c39901e087ceebae2733857248de81476bd8 ] If a nohz_full CPU is looping in the kernel, the scheduling-clock tick might nevertheless remain disabled. In !PREEMPT kernels, this can prevent RCU's attempts to enlist the aid of that CPU's executions of cond_resched(), which can in turn result in an arbitrarily delayed grace period and thus an OOM. RCU therefore needs a way to enable a holdout nohz_full CPU's scheduler-clock interrupt. This commit therefore provides a new TICK_DEP_BIT_RCU value which RCU can pass to tick_dep_set_cpu() and friends to force on the scheduler-clock interrupt for a specified CPU or task. In some cases, rcutorture needs to turn on the scheduler-clock tick, so this commit also exports the relevant symbols to GPL-licensed modules. Signed-off-by: Frederic Weisbecker Signed-off-by: Paul E. McKenney Stable-dep-of: 58d766824264 ("tick/nohz: Fix cpu_is_hotpluggable() by checking with nohz subsystem") Signed-off-by: Sasha Levin

SUNRPC: remove the maximum number of retries in call_bind_status

2023-05-17T09:13:19+00:00

[ Upstream commit 691d0b782066a6eeeecbfceb7910a8f6184e6105 ] Currently call_bind_status places a hard limit of 3 to the number of retries on EACCES error. This limit was done to prevent NLM unlock requests from being hang forever when the server keeps returning garbage. However this change causes problem for cases when NLM service takes longer than 9 seconds to register with the port mapper after a restart. This patch removes this hard coded limit and let the RPC handles the retry based on the standard hard/soft task semantics. Fixes: 0b760113a3a1 ("NLM: Don't hang forever on NLM unlock requests") Reported-by: Helen Chao Tested-by: Helen Chao Signed-off-by: Dai Ngo Reviewed-by: Jeff Layton Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin

linux/vt_buffer.h: allow either builtin or modular for macros

2023-05-17T09:13:15+00:00

[ Upstream commit 2b76ffe81e32afd6d318dc4547e2ba8c46207b77 ] Fix build errors on ARCH=alpha when CONFIG_MDA_CONSOLE=m. This allows the ARCH macros to be the only ones defined. In file included from ../drivers/video/console/mdacon.c:37: ../arch/alpha/include/asm/vga.h:17:40: error: expected identifier or '(' before 'volatile' 17 | static inline void scr_writew(u16 val, volatile u16 *addr) | ^~~~~~~~ ../include/linux/vt_buffer.h:24:34: note: in definition of macro 'scr_writew' 24 | #define scr_writew(val, addr) (*(addr) = (val)) | ^~~~ ../include/linux/vt_buffer.h:24:40: error: expected ')' before '=' token 24 | #define scr_writew(val, addr) (*(addr) = (val)) | ^ ../arch/alpha/include/asm/vga.h:17:20: note: in expansion of macro 'scr_writew' 17 | static inline void scr_writew(u16 val, volatile u16 *addr) | ^~~~~~~~~~ ../arch/alpha/include/asm/vga.h:25:29: error: expected identifier or '(' before 'volatile' 25 | static inline u16 scr_readw(volatile const u16 *addr) | ^~~~~~~~ Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Randy Dunlap Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: dri-devel@lists.freedesktop.org Cc: linux-fbdev@vger.kernel.org Link: https://lore.kernel.org/r/20230329021529.16188-1-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

netfilter: nf_tables: don't write table validation state without mutex

2023-05-17T09:13:14+00:00

[ Upstream commit 9a32e9850686599ed194ccdceb6cd3dd56b2d9b9 ] The ->cleanup callback needs to be removed, this doesn't work anymore as the transaction mutex is already released in the ->abort function. Just do it after a successful validation pass, this either happens from commit or abort phases where transaction mutex is held. Fixes: f102d66b335a ("netfilter: nf_tables: use dedicated mutex to guard transactions") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin

debugfs: regset32: Add Runtime PM support

2023-05-17T09:13:06+00:00

commit 30332eeefec8f83afcea00c360f99ef64b87f220 upstream. Hardware registers of devices under control of power management cannot be accessed at all times. If such a device is suspended, register accesses may lead to undefined behavior, like reading bogus values, or causing exceptions or system lock-ups. Extend struct debugfs_regset32 with an optional field to let device drivers specify the device the registers in the set belong to. This allows debugfs_show_regset32() to make sure the device is resumed while its registers are being read. Signed-off-by: Geert Uytterhoeven Reviewed-by: Niklas Söderlund Reviewed-by: Greg Kroah-Hartman Acked-by: Rafael J. Wysocki Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman

ftrace: Mark get_lock_parent_ip() __always_inline

2023-04-20T10:04:39+00:00

commit ea65b41807a26495ff2a73dd8b1bab2751940887 upstream. If the compiler decides not to inline this function then preemption tracing will always show an IP inside the preemption disabling path and never the function actually calling preempt_{enable,disable}. Link: https://lore.kernel.org/linux-trace-kernel/20230327173647.1690849-1-john@metanate.com Cc: Masami Hiramatsu Cc: Mark Rutland Cc: stable@vger.kernel.org Fixes: f904f58263e1d ("sched/debug: Fix preempt_disable_ip recording for preempt_disable()") Signed-off-by: John Keeping Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman