From 52cfc23e831fda2e294d32e08fe359dcf7d05c55 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Tue, 4 Jun 2013 17:09:36 -0400 Subject: [PATCH] xen/time: Don't leak interrupt name when offlining. When the user does: echo 0 > /sys/devices/system/cpu/cpu1/online echo 1 > /sys/devices/system/cpu/cpu1/online kmemleak reports: kmemleak: 7 new suspected memory leaks (see /sys/kernel/debug/kmemleak) One of the leaks is from xen/time: unreferenced object 0xffff88003fa51280 (size 32): comm "swapper/0", pid 1, jiffies 4294667339 (age 1027.789s) hex dump (first 32 bytes): 74 69 6d 65 72 31 00 00 00 00 00 00 00 00 00 00 timer1.......... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmemleak_alloc+0x21/0x50 [] __kmalloc_track_caller+0xec/0x2a0 [] kvasprintf+0x5b/0x90 [] kasprintf+0x38/0x40 [] xen_setup_timer+0x51/0xf0 [] xen_cpu_up+0x5f/0x3e8 [] _cpu_up+0xd1/0x14b [] cpu_up+0xd9/0xec [] smp_init+0x4b/0xa3 [] kernel_init_freeable+0xdb/0x1e6 [] kernel_init+0x9/0xf0 [] ret_from_fork+0x7c/0xb0 [] 0xffffffffffffffff This patch fixes it by stashing away the 'name' in the per-cpu data structure and freeing it when offlining the CPU. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/time.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index 5190687ca569..011f1bf85765 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -402,7 +403,7 @@ static irqreturn_t xen_timer_interrupt(int irq, void *dev_id) void xen_setup_timer(int cpu) { - const char *name; + char *name; struct clock_event_device *evt; int irq; @@ -425,6 +426,7 @@ void xen_setup_timer(int cpu) evt->cpumask = cpumask_of(cpu); evt->irq = irq; + per_cpu(xen_clock_events, cpu).name = name; } void xen_teardown_timer(int cpu) @@ -434,6 +436,8 @@ void xen_teardown_timer(int cpu) evt = &per_cpu(xen_clock_events, cpu).evt; unbind_from_irqhandler(evt->irq, NULL); evt->irq = -1; + kfree(per_cpu(xen_clock_events, cpu).name); + per_cpu(xen_clock_events, cpu).name = NULL; } void xen_setup_cpu_clockevents(void) -- 2.39.5