From c96f5471ce7d2aefd0dda560cc23f08ab00bc65d Mon Sep 17 00:00:00 2001 From: Josh Snyder Date: Mon, 18 Dec 2017 16:15:10 +0000 Subject: delayacct: Account blkio completion on the correct task Before commit: e33a9bba85a8 ("sched/core: move IO scheduling accounting from io_schedule_timeout() into scheduler") delayacct_blkio_end() was called after context-switching into the task which completed I/O. This resulted in double counting: the task would account a delay both waiting for I/O and for time spent in the runqueue. With e33a9bba85a8, delayacct_blkio_end() is called by try_to_wake_up(). In ttwu, we have not yet context-switched. This is more correct, in that the delay accounting ends when the I/O is complete. But delayacct_blkio_end() relies on 'get_current()', and we have not yet context-switched into the task whose I/O completed. This results in the wrong task having its delay accounting statistics updated. Instead of doing that, pass the task_struct being woken to delayacct_blkio_end(), so that it can update the statistics of the correct task. Signed-off-by: Josh Snyder Acked-by: Tejun Heo Acked-by: Balbir Singh Cc: Cc: Brendan Gregg Cc: Jens Axboe Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-block@vger.kernel.org Fixes: e33a9bba85a8 ("sched/core: move IO scheduling accounting from io_schedule_timeout() into scheduler") Link: http://lkml.kernel.org/r/1513613712-571-1-git-send-email-joshs@netflix.com Signed-off-by: Ingo Molnar --- include/linux/delayacct.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/delayacct.h b/include/linux/delayacct.h index 4178d2493547..5e335b6203f4 100644 --- a/include/linux/delayacct.h +++ b/include/linux/delayacct.h @@ -71,7 +71,7 @@ extern void delayacct_init(void); extern void __delayacct_tsk_init(struct task_struct *); extern void __delayacct_tsk_exit(struct task_struct *); extern void __delayacct_blkio_start(void); -extern void __delayacct_blkio_end(void); +extern void __delayacct_blkio_end(struct task_struct *); extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *); extern __u64 __delayacct_blkio_ticks(struct task_struct *); extern void __delayacct_freepages_start(void); @@ -122,10 +122,10 @@ static inline void delayacct_blkio_start(void) __delayacct_blkio_start(); } -static inline void delayacct_blkio_end(void) +static inline void delayacct_blkio_end(struct task_struct *p) { if (current->delays) - __delayacct_blkio_end(); + __delayacct_blkio_end(p); delayacct_clear_flag(DELAYACCT_PF_BLKIO); } @@ -169,7 +169,7 @@ static inline void delayacct_tsk_free(struct task_struct *tsk) {} static inline void delayacct_blkio_start(void) {} -static inline void delayacct_blkio_end(void) +static inline void delayacct_blkio_end(struct task_struct *p) {} static inline int delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) -- cgit v1.2.3 From 6cfb521ac0d5b97470883ff9b7facae264b7ab12 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 16 Jan 2018 12:52:28 -0800 Subject: module: Add retpoline tag to VERMAGIC Add a marker for retpoline to the module VERMAGIC. This catches the case when a non RETPOLINE compiled module gets loaded into a retpoline kernel, making it insecure. It doesn't handle the case when retpoline has been runtime disabled. Even in this case the match of the retcompile status will be enforced. This implies that even with retpoline run time disabled all modules loaded need to be recompiled. Signed-off-by: Andi Kleen Signed-off-by: Thomas Gleixner Reviewed-by: Greg Kroah-Hartman Acked-by: David Woodhouse Cc: rusty@rustcorp.com.au Cc: arjan.van.de.ven@intel.com Cc: jeyu@kernel.org Cc: torvalds@linux-foundation.org Link: https://lkml.kernel.org/r/20180116205228.4890-1-andi@firstfloor.org --- include/linux/vermagic.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/vermagic.h b/include/linux/vermagic.h index bae807eb2933..853291714ae0 100644 --- a/include/linux/vermagic.h +++ b/include/linux/vermagic.h @@ -31,11 +31,17 @@ #else #define MODULE_RANDSTRUCT_PLUGIN #endif +#ifdef RETPOLINE +#define MODULE_VERMAGIC_RETPOLINE "retpoline " +#else +#define MODULE_VERMAGIC_RETPOLINE "" +#endif #define VERMAGIC_STRING \ UTS_RELEASE " " \ MODULE_VERMAGIC_SMP MODULE_VERMAGIC_PREEMPT \ MODULE_VERMAGIC_MODULE_UNLOAD MODULE_VERMAGIC_MODVERSIONS \ MODULE_ARCH_VERMAGIC \ - MODULE_RANDSTRUCT_PLUGIN + MODULE_RANDSTRUCT_PLUGIN \ + MODULE_VERMAGIC_RETPOLINE -- cgit v1.2.3 From a3d6c976f71902388e444594daa902032b5a45fa Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Thu, 18 Jan 2018 16:34:08 -0800 Subject: sparse doesn't support struct randomization Without this patch, I drown in a sea of unknown attribute warnings Link: http://lkml.kernel.org/r/20180117024539.27354-1-willy@infradead.org Signed-off-by: Matthew Wilcox Acked-by: Kees Cook Cc: Ingo Molnar Cc: Josh Poimboeuf Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/compiler-gcc.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 2272ded07496..631354acfa72 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -219,7 +219,7 @@ /* Mark a function definition as prohibited from being cloned. */ #define __noclone __attribute__((__noclone__, __optimize__("no-tracer"))) -#ifdef RANDSTRUCT_PLUGIN +#if defined(RANDSTRUCT_PLUGIN) && !defined(__CHECKER__) #define __randomize_layout __attribute__((randomize_layout)) #define __no_randomize_layout __attribute__((no_randomize_layout)) #endif -- cgit v1.2.3