Revision 8cf66504210d308a35cca35fe9c310b1241f9fa7 authored by Qian Cai on 11 July 2019, 16:17:45 UTC, committed by Linus Torvalds on 21 July 2019, 16:57:13 UTC
The commit b3aa14f02254 ("iommu: remove the mapping_error dma_map_ops
method") incorrectly changed the checking from dma_ops_alloc_iova() in
map_sg() causes a crash under memory pressure as dma_ops_alloc_iova()
never return DMA_MAPPING_ERROR on failure but 0, so the error handling
is all wrong.

   kernel BUG at drivers/iommu/iova.c:801!
    Workqueue: kblockd blk_mq_run_work_fn
    RIP: 0010:iova_magazine_free_pfns+0x7d/0xc0
    Call Trace:
     free_cpu_cached_iovas+0xbd/0x150
     alloc_iova_fast+0x8c/0xba
     dma_ops_alloc_iova.isra.6+0x65/0xa0
     map_sg+0x8c/0x2a0
     scsi_dma_map+0xc6/0x160
     pqi_aio_submit_io+0x1f6/0x440 [smartpqi]
     pqi_scsi_queue_command+0x90c/0xdd0 [smartpqi]
     scsi_queue_rq+0x79c/0x1200
     blk_mq_dispatch_rq_list+0x4dc/0xb70
     blk_mq_sched_dispatch_requests+0x249/0x310
     __blk_mq_run_hw_queue+0x128/0x200
     blk_mq_run_work_fn+0x27/0x30
     process_one_work+0x522/0xa10
     worker_thread+0x63/0x5b0
     kthread+0x1d2/0x1f0
     ret_from_fork+0x22/0x40

Fixes: b3aa14f02254 ("iommu: remove the mapping_error dma_map_ops method")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 618381f
Raw File
compat_binfmt_elf.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * 32-bit compatibility support for ELF format executables and core dumps.
 *
 * Copyright (C) 2007 Red Hat, Inc.  All rights reserved.
 *
 * Red Hat Author: Roland McGrath.
 *
 * This file is used in a 64-bit kernel that wants to support 32-bit ELF.
 * asm/elf.h is responsible for defining the compat_* and COMPAT_* macros
 * used below, with definitions appropriate for 32-bit ABI compatibility.
 *
 * We use macros to rename the ABI types and machine-dependent
 * functions used in binfmt_elf.c to compat versions.
 */

#include <linux/elfcore-compat.h>
#include <linux/time.h>

/*
 * Rename the basic ELF layout types to refer to the 32-bit class of files.
 */
#undef	ELF_CLASS
#define ELF_CLASS	ELFCLASS32

#undef	elfhdr
#undef	elf_phdr
#undef	elf_shdr
#undef	elf_note
#undef	elf_addr_t
#define elfhdr		elf32_hdr
#define elf_phdr	elf32_phdr
#define elf_shdr	elf32_shdr
#define elf_note	elf32_note
#define elf_addr_t	Elf32_Addr

/*
 * Some data types as stored in coredump.
 */
#define user_long_t		compat_long_t
#define user_siginfo_t		compat_siginfo_t
#define copy_siginfo_to_user	copy_siginfo_to_user32

/*
 * The machine-dependent core note format types are defined in elfcore-compat.h,
 * which requires asm/elf.h to define compat_elf_gregset_t et al.
 */
#define elf_prstatus	compat_elf_prstatus
#define elf_prpsinfo	compat_elf_prpsinfo

#undef ns_to_timeval
#define ns_to_timeval ns_to_old_timeval32

/*
 * To use this file, asm/elf.h must define compat_elf_check_arch.
 * The other following macros can be defined if the compat versions
 * differ from the native ones, or omitted when they match.
 */

#undef	ELF_ARCH
#undef	elf_check_arch
#define	elf_check_arch	compat_elf_check_arch

#ifdef	COMPAT_ELF_PLATFORM
#undef	ELF_PLATFORM
#define	ELF_PLATFORM		COMPAT_ELF_PLATFORM
#endif

#ifdef	COMPAT_ELF_HWCAP
#undef	ELF_HWCAP
#define	ELF_HWCAP		COMPAT_ELF_HWCAP
#endif

#ifdef	COMPAT_ELF_HWCAP2
#undef	ELF_HWCAP2
#define	ELF_HWCAP2		COMPAT_ELF_HWCAP2
#endif

#ifdef	COMPAT_ARCH_DLINFO
#undef	ARCH_DLINFO
#define	ARCH_DLINFO		COMPAT_ARCH_DLINFO
#endif

#ifdef	COMPAT_ELF_ET_DYN_BASE
#undef	ELF_ET_DYN_BASE
#define	ELF_ET_DYN_BASE		COMPAT_ELF_ET_DYN_BASE
#endif

#ifdef COMPAT_ELF_EXEC_PAGESIZE
#undef	ELF_EXEC_PAGESIZE
#define	ELF_EXEC_PAGESIZE	COMPAT_ELF_EXEC_PAGESIZE
#endif

#ifdef	COMPAT_ELF_PLAT_INIT
#undef	ELF_PLAT_INIT
#define	ELF_PLAT_INIT		COMPAT_ELF_PLAT_INIT
#endif

#ifdef	COMPAT_SET_PERSONALITY
#undef	SET_PERSONALITY
#define	SET_PERSONALITY		COMPAT_SET_PERSONALITY
#endif

#ifdef	compat_start_thread
#undef	start_thread
#define	start_thread		compat_start_thread
#endif

#ifdef	compat_arch_setup_additional_pages
#undef	ARCH_HAS_SETUP_ADDITIONAL_PAGES
#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
#undef	arch_setup_additional_pages
#define	arch_setup_additional_pages compat_arch_setup_additional_pages
#endif

/*
 * Rename a few of the symbols that binfmt_elf.c will define.
 * These are all local so the names don't really matter, but it
 * might make some debugging less confusing not to duplicate them.
 */
#define elf_format		compat_elf_format
#define init_elf_binfmt		init_compat_elf_binfmt
#define exit_elf_binfmt		exit_compat_elf_binfmt

/*
 * We share all the actual code with the native (64-bit) version.
 */
#include "binfmt_elf.c"
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