From b85fffec7f5ba1c43171c63c046a97bac30a4561 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Tue, 4 Jun 2013 16:47:17 -0400 Subject: [PATCH] xen/smp: 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) unreferenced object 0xffff88003fa51240 (size 32): comm "swapper/0", pid 1, jiffies 4294667339 (age 1027.789s) hex dump (first 32 bytes): 72 65 73 63 68 65 64 31 00 00 00 00 00 00 00 00 resched1........ 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_smp_intr_init+0x41/0x2c0 [] xen_cpu_up+0x393/0x3e8 [] _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 some of it by using the 'struct xen_common_irq->name' field to stash away the char so that it can be freed when the interrupt line is destroyed. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/smp.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 6a483cd..37fbe71 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -107,19 +107,27 @@ static void xen_smp_intr_free(unsigned int cpu) if (per_cpu(xen_resched_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL); per_cpu(xen_resched_irq, cpu).irq = -1; + kfree(per_cpu(xen_resched_irq, cpu).name); + per_cpu(xen_resched_irq, cpu).name = NULL; } if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL); per_cpu(xen_callfunc_irq, cpu).irq = -1; + kfree(per_cpu(xen_callfunc_irq, cpu).name); + per_cpu(xen_callfunc_irq, cpu).name = NULL; } if (per_cpu(xen_debug_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL); per_cpu(xen_debug_irq, cpu).irq = -1; + kfree(per_cpu(xen_debug_irq, cpu).name); + per_cpu(xen_debug_irq, cpu).name = NULL; } if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq, NULL); per_cpu(xen_callfuncsingle_irq, cpu).irq = -1; + kfree(per_cpu(xen_callfuncsingle_irq, cpu).name); + per_cpu(xen_callfuncsingle_irq, cpu).name = NULL; } if (xen_hvm_domain()) return; @@ -127,12 +135,14 @@ static void xen_smp_intr_free(unsigned int cpu) if (per_cpu(xen_irq_work, cpu).irq >= 0) { unbind_from_irqhandler(per_cpu(xen_irq_work, cpu).irq, NULL); per_cpu(xen_irq_work, cpu).irq = -1; + kfree(per_cpu(xen_irq_work, cpu).name); + per_cpu(xen_irq_work, cpu).name = NULL; } }; static int xen_smp_intr_init(unsigned int cpu) { int rc; - const char *resched_name, *callfunc_name, *debug_name; + char *resched_name, *callfunc_name, *debug_name; resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu); rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR, @@ -144,6 +154,7 @@ static int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_resched_irq, cpu).irq = rc; + per_cpu(xen_resched_irq, cpu).name = resched_name; callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu); rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR, @@ -155,6 +166,7 @@ static int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_callfunc_irq, cpu).irq = rc; + per_cpu(xen_callfunc_irq, cpu).name = callfunc_name; debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu); rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt, @@ -163,6 +175,7 @@ static int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_debug_irq, cpu).irq = rc; + per_cpu(xen_debug_irq, cpu).name = debug_name; callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu); rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR, @@ -174,6 +187,7 @@ static int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_callfuncsingle_irq, cpu).irq = rc; + per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name; /* * The IRQ worker on PVHVM goes through the native path and uses the @@ -192,6 +206,7 @@ static int xen_smp_intr_init(unsigned int cpu) if (rc < 0) goto fail; per_cpu(xen_irq_work, cpu).irq = rc; + per_cpu(xen_irq_work, cpu).name = callfunc_name; return 0; -- 2.7.4