powerpc/msi: Free the bitmap if it was slab allocated (cb2d3883) · Commits · 戴 / test

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: [<c00000000003eebc>] .zalloc_maybe_bootmem+0x3c/0x380 [<c000000000042d6c>] .msi_bitmap_alloc+0x3c/0xb0 [<c000000000a9aff8>] .msi_bitmap_selftest+0x30/0x2b4 [<c0000000000090f4>] .do_one_initcall+0xd4/0x270 [<c000000000a8e250>] .kernel_init_freeable+0x1a0/0x280 [<c000000000009b5c>] .kernel_init+0x1c/0x120 [<c000000000007fbc>] .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 <kda@linux-powerpc.org> Reviewed-by:

Catalin Marinas <catalin.marinas@arm.com> [mpe: Reword changelog & use bitmap_from_slab in the if] Signed-off-by:

Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/msi_bitmap.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -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);

arch/powerpc/sysdev/msi_bitmap.c

+12 −4

Original line number	Diff line number	Diff line
		@@ -11,6 +11,7 @@
		#include <linux/slab.h>
		#include <linux/kernel.h>
		#include <linux/bitmap.h>
		#include <linux/bootmem.h>
		#include <asm/msi_bitmap.h>
		#include <asm/setup.h>

		@@ -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)

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