From cb2d3883c6033831e2a93b396fcc43033108409c Mon Sep 17 00:00:00 2001 From: Denis Kirjanov Date: Wed, 16 Sep 2015 22:26:14 +0300 Subject: [PATCH] powerpc/msi: Free the bitmap if it was slab allocated During the MSI bitmap test on boot kmemleak spews the following trace: unreferenced object 0xc00000016e86c900 (size 64): comm "swapper/0", pid 1, jiffies 4294893173 (age 518.024s) hex dump (first 32 bytes): 00 00 01 ff 7f ff 7f 37 00 00 00 00 00 00 00 00 .......7........ ff ff ff ff ff ff ff ff 01 ff ff ff ff ff ff ff ................ backtrace: [] .zalloc_maybe_bootmem+0x3c/0x380 [] .msi_bitmap_alloc+0x3c/0xb0 [] .msi_bitmap_selftest+0x30/0x2b4 [] .do_one_initcall+0xd4/0x270 [] .kernel_init_freeable+0x1a0/0x280 [] .kernel_init+0x1c/0x120 [] .ret_from_kernel_thread+0x58/0x9c Add a flag to msi_bitmap for tracking allocations from slab and memblock so we can properly free/handle memory in msi_bitmap_free(). Signed-off-by: Denis Kirjanov Reviewed-by: Catalin Marinas [mpe: Reword changelog & use bitmap_from_slab in the if] Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/msi_bitmap.h | 1 + arch/powerpc/sysdev/msi_bitmap.c | 16 ++++++++++++---- 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/include/asm/msi_bitmap.h b/arch/powerpc/include/asm/msi_bitmap.h index 97ac3f46ae0d..1ec7125551f1 100644 --- a/arch/powerpc/include/asm/msi_bitmap.h +++ b/arch/powerpc/include/asm/msi_bitmap.h @@ -19,6 +19,7 @@ struct msi_bitmap { unsigned long *bitmap; spinlock_t lock; unsigned int irq_count; + bool bitmap_from_slab; }; int msi_bitmap_alloc_hwirqs(struct msi_bitmap *bmp, int num); diff --git a/arch/powerpc/sysdev/msi_bitmap.c b/arch/powerpc/sysdev/msi_bitmap.c index 73b64c73505b..1a826f3b4424 100644 --- a/arch/powerpc/sysdev/msi_bitmap.c +++ b/arch/powerpc/sysdev/msi_bitmap.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -122,7 +123,15 @@ int msi_bitmap_alloc(struct msi_bitmap *bmp, unsigned int irq_count, size = BITS_TO_LONGS(irq_count) * sizeof(long); pr_debug("msi_bitmap: allocator bitmap size is 0x%x bytes\n", size); - bmp->bitmap = zalloc_maybe_bootmem(size, GFP_KERNEL); + bmp->bitmap_from_slab = slab_is_available(); + if (bmp->bitmap_from_slab) + bmp->bitmap = kzalloc(size, GFP_KERNEL); + else { + bmp->bitmap = memblock_virt_alloc(size, 0); + /* the bitmap won't be freed from memblock allocator */ + kmemleak_not_leak(bmp->bitmap); + } + if (!bmp->bitmap) { pr_debug("msi_bitmap: ENOMEM allocating allocator bitmap!\n"); return -ENOMEM; @@ -138,7 +147,8 @@ int msi_bitmap_alloc(struct msi_bitmap *bmp, unsigned int irq_count, void msi_bitmap_free(struct msi_bitmap *bmp) { - /* we can't free the bitmap we don't know if it's bootmem etc. */ + if (bmp->bitmap_from_slab) + kfree(bmp->bitmap); of_node_put(bmp->of_node); bmp->bitmap = NULL; } @@ -203,8 +213,6 @@ static void __init test_basics(void) /* Clients may WARN_ON bitmap == NULL for "not-allocated" */ WARN_ON(bmp.bitmap != NULL); - - kfree(bmp.bitmap); } static void __init test_of_node(void) -- 2.20.1