From 27c379f7f89a4d558c685b5d89b5ba2fe79ae701 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Fri, 10 Sep 2010 13:47:29 +0200 Subject: generic-ipi: Fix deadlock in __smp_call_function_single Just got my 6 way machine to a state where cpu 0 is in an endless loop within __smp_call_function_single. All other cpus are idle. The call trace on cpu 0 looks like this: __smp_call_function_single scheduler_tick update_process_times tick_sched_timer __run_hrtimer hrtimer_interrupt clock_comparator_work do_extint ext_int_handler ----> timer irq cpu_idle __smp_call_function_single() got called from nohz_balancer_kick() (inlined) with the remote cpu being 1, wait being 0 and the per cpu variable remote_sched_softirq_cb (call_single_data) of the current cpu (0). Then it loops forever when it tries to grab the lock of the call_single_data, since it is already locked and enqueued on cpu 0. My theory how this could have happened: for some reason the scheduler decided to call __smp_call_function_single() on it's own cpu, and sends an IPI to itself. The interrupt stays pending since IRQs are disabled. If then the hypervisor schedules the cpu away it might happen that upon rescheduling both the IPI and the timer IRQ are pending. If then interrupts are enabled again it depends which one gets scheduled first. If the timer interrupt gets delivered first we end up with the local deadlock as seen in the calltrace above. Let's make __smp_call_function_single() check if the target cpu is the current cpu and execute the function immediately just like smp_call_function_single does. That should prevent at least the scenario described here. It might also be that the scheduler is not supposed to call __smp_call_function_single with the remote cpu being the current cpu, but that is a different issue. Signed-off-by: Heiko Carstens Acked-by: Peter Zijlstra Acked-by: Jens Axboe Cc: Venkatesh Pallipadi Cc: Suresh Siddha LKML-Reference: <20100910114729.GB2827@osiris.boeblingen.de.ibm.com> Signed-off-by: Ingo Molnar --- kernel/smp.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/smp.c b/kernel/smp.c index 75c970c715d3..ed6aacfcb7ef 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -365,9 +365,10 @@ call: EXPORT_SYMBOL_GPL(smp_call_function_any); /** - * __smp_call_function_single(): Run a function on another CPU + * __smp_call_function_single(): Run a function on a specific CPU * @cpu: The CPU to run on. * @data: Pre-allocated and setup data structure + * @wait: If true, wait until function has completed on specified CPU. * * Like smp_call_function_single(), but allow caller to pass in a * pre-allocated data structure. Useful for embedding @data inside @@ -376,8 +377,10 @@ EXPORT_SYMBOL_GPL(smp_call_function_any); void __smp_call_function_single(int cpu, struct call_single_data *data, int wait) { - csd_lock(data); + unsigned int this_cpu; + unsigned long flags; + this_cpu = get_cpu(); /* * Can deadlock when called with interrupts disabled. * We allow cpu's that are not yet online though, as no one else can @@ -387,7 +390,15 @@ void __smp_call_function_single(int cpu, struct call_single_data *data, WARN_ON_ONCE(cpu_online(smp_processor_id()) && wait && irqs_disabled() && !oops_in_progress); - generic_exec_single(cpu, data, wait); + if (cpu == this_cpu) { + local_irq_save(flags); + data->func(data->info); + local_irq_restore(flags); + } else { + csd_lock(data); + generic_exec_single(cpu, data, wait); + } + put_cpu(); } /** -- cgit v1.2.3 From 399f1e30ac17b77d383444aff480c7390f5adf2a Mon Sep 17 00:00:00 2001 From: "Ira W. Snyder" Date: Thu, 30 Sep 2010 15:15:27 -0700 Subject: kfifo: fix scatterlist usage The kfifo_dma family of functions use sg_mark_end() on the last element in their scatterlist. This forces use of a fresh scatterlist for each DMA operation, which makes recycling a single scatterlist impossible. Change the behavior of the kfifo_dma functions to match the usage of the dma_map_sg function. This means that users must respect the returned nents value. The sample code is updated to reflect the change. This bug is trivial to cause: call kfifo_dma_in_prepare() such that it prepares a scatterlist with a single entry comprising the whole fifo. This is the case when you map the entirety of a newly created empty fifo. This causes the setup_sgl() function to mark the first scatterlist entry as the end of the chain, no matter what comes after it. Afterwards, add and remove some data from the fifo such that another call to kfifo_dma_in_prepare() will create two scatterlist entries. It returns nents=2. However, due to the previous sg_mark_end() call, sg_is_last() will now return true for the first scatterlist element. This causes the sample code to print a single scatterlist element when it should print two. By removing the call to sg_mark_end(), we make the API as similar as possible to the DMA mapping API. All users are required to respect the returned nents. Signed-off-by: Ira W. Snyder Cc: Stefani Seibold Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kfifo.c | 2 -- samples/kfifo/dma-example.c | 17 +++++++++-------- 2 files changed, 9 insertions(+), 10 deletions(-) (limited to 'kernel') diff --git a/kernel/kfifo.c b/kernel/kfifo.c index 6b5580c57644..01a0700e873f 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -365,8 +365,6 @@ static unsigned int setup_sgl(struct __kfifo *fifo, struct scatterlist *sgl, n = setup_sgl_buf(sgl, fifo->data + off, nents, l); n += setup_sgl_buf(sgl + n, fifo->data, nents - n, len - l); - if (n) - sg_mark_end(sgl + n - 1); return n; } diff --git a/samples/kfifo/dma-example.c b/samples/kfifo/dma-example.c index ee03a4f0b64f..06473791c08a 100644 --- a/samples/kfifo/dma-example.c +++ b/samples/kfifo/dma-example.c @@ -24,6 +24,7 @@ static int __init example_init(void) { int i; unsigned int ret; + unsigned int nents; struct scatterlist sg[10]; printk(KERN_INFO "DMA fifo test start\n"); @@ -61,9 +62,9 @@ static int __init example_init(void) * byte at the beginning, after the kfifo_skip(). */ sg_init_table(sg, ARRAY_SIZE(sg)); - ret = kfifo_dma_in_prepare(&fifo, sg, ARRAY_SIZE(sg), FIFO_SIZE); - printk(KERN_INFO "DMA sgl entries: %d\n", ret); - if (!ret) { + nents = kfifo_dma_in_prepare(&fifo, sg, ARRAY_SIZE(sg), FIFO_SIZE); + printk(KERN_INFO "DMA sgl entries: %d\n", nents); + if (!nents) { /* fifo is full and no sgl was created */ printk(KERN_WARNING "error kfifo_dma_in_prepare\n"); return -EIO; @@ -71,7 +72,7 @@ static int __init example_init(void) /* receive data */ printk(KERN_INFO "scatterlist for receive:\n"); - for (i = 0; i < ARRAY_SIZE(sg); i++) { + for (i = 0; i < nents; i++) { printk(KERN_INFO "sg[%d] -> " "page_link 0x%.8lx offset 0x%.8x length 0x%.8x\n", @@ -91,16 +92,16 @@ static int __init example_init(void) kfifo_dma_in_finish(&fifo, ret); /* Prepare to transmit data, example: 8 bytes */ - ret = kfifo_dma_out_prepare(&fifo, sg, ARRAY_SIZE(sg), 8); - printk(KERN_INFO "DMA sgl entries: %d\n", ret); - if (!ret) { + nents = kfifo_dma_out_prepare(&fifo, sg, ARRAY_SIZE(sg), 8); + printk(KERN_INFO "DMA sgl entries: %d\n", nents); + if (!nents) { /* no data was available and no sgl was created */ printk(KERN_WARNING "error kfifo_dma_out_prepare\n"); return -EIO; } printk(KERN_INFO "scatterlist for transmit:\n"); - for (i = 0; i < ARRAY_SIZE(sg); i++) { + for (i = 0; i < nents; i++) { printk(KERN_INFO "sg[%d] -> " "page_link 0x%.8lx offset 0x%.8x length 0x%.8x\n", -- cgit v1.2.3 From 5336377d6225959624146629ce3fc88ee8ecda3d Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 5 Oct 2010 11:29:27 -0700 Subject: modules: Fix module_bug_list list corruption race With all the recent module loading cleanups, we've minimized the code that sits under module_mutex, fixing various deadlocks and making it possible to do most of the module loading in parallel. However, that whole conversion totally missed the rather obscure code that adds a new module to the list for BUG() handling. That code was doubly obscure because (a) the code itself lives in lib/bugs.c (for dubious reasons) and (b) it gets called from the architecture-specific "module_finalize()" rather than from generic code. Calling it from arch-specific code makes no sense what-so-ever to begin with, and is now actively wrong since that code isn't protected by the module loading lock any more. So this commit moves the "module_bug_{finalize,cleanup}()" calls away from the arch-specific code, and into the generic code - and in the process protects it with the module_mutex so that the list operations are now safe. Future fixups: - move the module list handling code into kernel/module.c where it belongs. - get rid of 'module_bug_list' and just use the regular list of modules (called 'modules' - imagine that) that we already create and maintain for other reasons. Reported-and-tested-by: Thomas Gleixner Cc: Rusty Russell Cc: Adrian Bunk Cc: Andrew Morton Cc: stable@kernel.org Signed-off-by: Linus Torvalds --- arch/avr32/kernel/module.c | 3 +-- arch/h8300/kernel/module.c | 3 +-- arch/mn10300/kernel/module.c | 3 +-- arch/parisc/kernel/module.c | 3 +-- arch/powerpc/kernel/module.c | 5 ----- arch/s390/kernel/module.c | 3 +-- arch/sh/kernel/module.c | 2 -- arch/x86/kernel/module.c | 3 +-- include/linux/module.h | 5 ++--- kernel/module.c | 4 ++++ lib/bug.c | 6 ++---- 11 files changed, 14 insertions(+), 26 deletions(-) (limited to 'kernel') diff --git a/arch/avr32/kernel/module.c b/arch/avr32/kernel/module.c index 98f94d041d9c..a727f54d64d6 100644 --- a/arch/avr32/kernel/module.c +++ b/arch/avr32/kernel/module.c @@ -314,10 +314,9 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, vfree(module->arch.syminfo); module->arch.syminfo = NULL; - return module_bug_finalize(hdr, sechdrs, module); + return 0; } void module_arch_cleanup(struct module *module) { - module_bug_cleanup(module); } diff --git a/arch/h8300/kernel/module.c b/arch/h8300/kernel/module.c index 0865e291c20d..db4953dc4e1b 100644 --- a/arch/h8300/kernel/module.c +++ b/arch/h8300/kernel/module.c @@ -112,10 +112,9 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, struct module *me) { - return module_bug_finalize(hdr, sechdrs, me); + return 0; } void module_arch_cleanup(struct module *mod) { - module_bug_cleanup(mod); } diff --git a/arch/mn10300/kernel/module.c b/arch/mn10300/kernel/module.c index 6aea7fd76993..196a111e2e29 100644 --- a/arch/mn10300/kernel/module.c +++ b/arch/mn10300/kernel/module.c @@ -206,7 +206,7 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, struct module *me) { - return module_bug_finalize(hdr, sechdrs, me); + return 0; } /* @@ -214,5 +214,4 @@ int module_finalize(const Elf_Ehdr *hdr, */ void module_arch_cleanup(struct module *mod) { - module_bug_cleanup(mod); } diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c index 159a2b81e90c..6e81bb596e5b 100644 --- a/arch/parisc/kernel/module.c +++ b/arch/parisc/kernel/module.c @@ -941,11 +941,10 @@ int module_finalize(const Elf_Ehdr *hdr, nsyms = newptr - (Elf_Sym *)symhdr->sh_addr; DEBUGP("NEW num_symtab %lu\n", nsyms); symhdr->sh_size = nsyms * sizeof(Elf_Sym); - return module_bug_finalize(hdr, sechdrs, me); + return 0; } void module_arch_cleanup(struct module *mod) { deregister_unwind_table(mod); - module_bug_cleanup(mod); } diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c index 477c663e0140..4ef93ae2235f 100644 --- a/arch/powerpc/kernel/module.c +++ b/arch/powerpc/kernel/module.c @@ -65,10 +65,6 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sect; int err; - err = module_bug_finalize(hdr, sechdrs, me); - if (err) - return err; - /* Apply feature fixups */ sect = find_section(hdr, sechdrs, "__ftr_fixup"); if (sect != NULL) @@ -101,5 +97,4 @@ int module_finalize(const Elf_Ehdr *hdr, void module_arch_cleanup(struct module *mod) { - module_bug_cleanup(mod); } diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c index 22cfd634c355..f7167ee4604c 100644 --- a/arch/s390/kernel/module.c +++ b/arch/s390/kernel/module.c @@ -407,10 +407,9 @@ int module_finalize(const Elf_Ehdr *hdr, { vfree(me->arch.syminfo); me->arch.syminfo = NULL; - return module_bug_finalize(hdr, sechdrs, me); + return 0; } void module_arch_cleanup(struct module *mod) { - module_bug_cleanup(mod); } diff --git a/arch/sh/kernel/module.c b/arch/sh/kernel/module.c index 43adddfe4c04..ae0be697a89e 100644 --- a/arch/sh/kernel/module.c +++ b/arch/sh/kernel/module.c @@ -149,13 +149,11 @@ int module_finalize(const Elf_Ehdr *hdr, int ret = 0; ret |= module_dwarf_finalize(hdr, sechdrs, me); - ret |= module_bug_finalize(hdr, sechdrs, me); return ret; } void module_arch_cleanup(struct module *mod) { - module_bug_cleanup(mod); module_dwarf_cleanup(mod); } diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c index e0bc186d7501..1c355c550960 100644 --- a/arch/x86/kernel/module.c +++ b/arch/x86/kernel/module.c @@ -239,11 +239,10 @@ int module_finalize(const Elf_Ehdr *hdr, apply_paravirt(pseg, pseg + para->sh_size); } - return module_bug_finalize(hdr, sechdrs, me); + return 0; } void module_arch_cleanup(struct module *mod) { alternatives_smp_module_del(mod); - module_bug_cleanup(mod); } diff --git a/include/linux/module.h b/include/linux/module.h index 8a6b9fdc7ffa..aace066bad8f 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -686,17 +686,16 @@ extern int module_sysfs_initialized; #ifdef CONFIG_GENERIC_BUG -int module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *, +void module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *, struct module *); void module_bug_cleanup(struct module *); #else /* !CONFIG_GENERIC_BUG */ -static inline int module_bug_finalize(const Elf_Ehdr *hdr, +static inline void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, struct module *mod) { - return 0; } static inline void module_bug_cleanup(struct module *mod) {} #endif /* CONFIG_GENERIC_BUG */ diff --git a/kernel/module.c b/kernel/module.c index d0b5f8db11b4..ccd641991842 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1537,6 +1537,7 @@ static int __unlink_module(void *_mod) { struct module *mod = _mod; list_del(&mod->list); + module_bug_cleanup(mod); return 0; } @@ -2625,6 +2626,7 @@ static struct module *load_module(void __user *umod, if (err < 0) goto ddebug; + module_bug_finalize(info.hdr, info.sechdrs, mod); list_add_rcu(&mod->list, &modules); mutex_unlock(&module_mutex); @@ -2650,6 +2652,8 @@ static struct module *load_module(void __user *umod, mutex_lock(&module_mutex); /* Unlink carefully: kallsyms could be walking list. */ list_del_rcu(&mod->list); + module_bug_cleanup(mod); + ddebug: if (!mod->taints) dynamic_debug_remove(info.debug); diff --git a/lib/bug.c b/lib/bug.c index 7cdfad88128f..19552096d16b 100644 --- a/lib/bug.c +++ b/lib/bug.c @@ -72,8 +72,8 @@ static const struct bug_entry *module_find_bug(unsigned long bugaddr) return NULL; } -int module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, - struct module *mod) +void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, + struct module *mod) { char *secstrings; unsigned int i; @@ -97,8 +97,6 @@ int module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, * could potentially lead to deadlock and thus be counter-productive. */ list_add(&mod->bug_list, &module_bug_list); - - return 0; } void module_bug_cleanup(struct module *mod) -- cgit v1.2.3 From a337fdac7a5622d1e6547f4b476c14dfe5a2c892 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Mon, 27 Sep 2010 20:32:19 +0200 Subject: HWPOISON: Copy si_addr_lsb to user The original hwpoison code added a new siginfo field si_addr_lsb to pass the granuality of the fault address to user space. Unfortunately this field was never copied to user space. Fix this here. I added explicit checks for the MCEERR codes to avoid having to patch all potential callers to initialize the field. Signed-off-by: Andi Kleen --- kernel/signal.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'kernel') diff --git a/kernel/signal.c b/kernel/signal.c index bded65187780..919562c3d6b7 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2214,6 +2214,14 @@ int copy_siginfo_to_user(siginfo_t __user *to, siginfo_t *from) err |= __put_user(from->si_addr, &to->si_addr); #ifdef __ARCH_SI_TRAPNO err |= __put_user(from->si_trapno, &to->si_trapno); +#endif +#ifdef BUS_MCEERR_AO + /* + * Other callers might not initialize the si_lsb field, + * so check explicitely for the right codes here. + */ + if (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO) + err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); #endif break; case __SI_CHLD: -- cgit v1.2.3 From 27b3d80a7b6adcf069b5e869e4efcc3a79f88a91 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 7 Oct 2010 12:59:29 -0700 Subject: sysctl: fix min/max handling in __do_proc_doulongvec_minmax() When proc_doulongvec_minmax() is used with an array of longs, and no min/max check requested (.extra1 or .extra2 being NULL), we dereference a NULL pointer for the second element of the array. Noticed while doing some changes in network stack for the "16TB problem" Fix is to not change min & max pointers in __do_proc_doulongvec_minmax(), so that all elements of the vector share an unique min/max limit, like proc_dointvec_minmax(). [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Eric Dumazet Cc: "Eric W. Biederman" Cc: Americo Wang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/sysctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/sysctl.c b/kernel/sysctl.c index f88552c6d227..3a45c224770f 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -2485,7 +2485,7 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int kbuf[left] = 0; } - for (; left && vleft--; i++, min++, max++, first=0) { + for (; left && vleft--; i++, first = 0) { unsigned long val; if (write) { -- cgit v1.2.3 From ad0cf3478de8677f720ee06393b3147819568d6a Mon Sep 17 00:00:00 2001 From: John Blackwood Date: Tue, 28 Sep 2010 18:03:11 -0400 Subject: perf: Fix incorrect copy_from_user() usage perf events: repair incorrect use of copy_from_user This makes the perf_event_period() return 0 instead of -EFAULT on success. Signed-off-by: John Blackwood Signed-off-by: Joe Korty Acked-by: Peter Zijlstra LKML-Reference: <20100928220311.GA18145@tsunami.ccur.com> Signed-off-by: Ingo Molnar --- kernel/perf_event.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/perf_event.c b/kernel/perf_event.c index db5b56064687..b98bed3d8182 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -2202,15 +2202,13 @@ static void perf_event_for_each(struct perf_event *event, static int perf_event_period(struct perf_event *event, u64 __user *arg) { struct perf_event_context *ctx = event->ctx; - unsigned long size; int ret = 0; u64 value; if (!event->attr.sample_period) return -EINVAL; - size = copy_from_user(&value, arg, sizeof(value)); - if (size != sizeof(value)) + if (copy_from_user(&value, arg, sizeof(value))) return -EFAULT; if (!value) -- cgit v1.2.3 From d01343244abdedd18303d0323b518ed9cdcb1988 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Tue, 12 Oct 2010 12:06:43 -0400 Subject: ring-buffer: Fix typo of time extends per page Time stamps for the ring buffer are created by the difference between two events. Each page of the ring buffer holds a full 64 bit timestamp. Each event has a 27 bit delta stamp from the last event. The unit of time is nanoseconds, so 27 bits can hold ~134 milliseconds. If two events happen more than 134 milliseconds apart, a time extend is inserted to add more bits for the delta. The time extend has 59 bits, which is good for ~18 years. Currently the time extend is committed separately from the event. If an event is discarded before it is committed, due to filtering, the time extend still exists. If all events are being filtered, then after ~134 milliseconds a new time extend will be added to the buffer. This can only happen till the end of the page. Since each page holds a full timestamp, there is no reason to add a time extend to the beginning of a page. Time extends can only fill a page that has actual data at the beginning, so there is no fear that time extends will fill more than a page without any data. When reading an event, a loop is made to skip over time extends since they are only used to maintain the time stamp and are never given to the caller. As a paranoid check to prevent the loop running forever, with the knowledge that time extends may only fill a page, a check is made that tests the iteration of the loop, and if the iteration is more than the number of time extends that can fit in a page a warning is printed and the ring buffer is disabled (all of ftrace is also disabled with it). There is another event type that is called a TIMESTAMP which can hold 64 bits of data in the theoretical case that two events happen 18 years apart. This code has not been implemented, but the name of this event exists, as well as the structure for it. The size of a TIMESTAMP is 16 bytes, where as a time extend is only 8 bytes. The macro used to calculate how many time extends can fit on a page used the TIMESTAMP size instead of the time extend size cutting the amount in half. The following test case can easily trigger the warning since we only need to have half the page filled with time extends to trigger the warning: # cd /sys/kernel/debug/tracing/ # echo function > current_tracer # echo 'common_pid < 0' > events/ftrace/function/filter # echo > trace # echo 1 > trace_marker # sleep 120 # cat trace Enabling the function tracer and then setting the filter to only trace functions where the process id is negative (no events), then clearing the trace buffer to ensure that we have nothing in the buffer, then write to trace_marker to add an event to the beginning of a page, sleep for 2 minutes (only 35 seconds is probably needed, but this guarantees the bug), and then finally reading the trace which will trigger the bug. This patch fixes the typo and prevents the false positive of that warning. Reported-by: Hans J. Koch Tested-by: Hans J. Koch Cc: Thomas Gleixner Cc: Stable Kernel Signed-off-by: Steven Rostedt --- kernel/trace/ring_buffer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 492197e2f86c..bca96377fd4e 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -405,7 +405,7 @@ static inline int test_time_stamp(u64 delta) #define BUF_MAX_DATA_SIZE (BUF_PAGE_SIZE - (sizeof(u32) * 2)) /* Max number of timestamps that can fit on a page */ -#define RB_TIMESTAMPS_PER_PAGE (BUF_PAGE_SIZE / RB_LEN_TIME_STAMP) +#define RB_TIMESTAMPS_PER_PAGE (BUF_PAGE_SIZE / RB_LEN_TIME_EXTEND) int ring_buffer_print_page_header(struct trace_seq *s) { -- cgit v1.2.3