On Wed, May 22, 2019 at 06:45:41PM +0800, John Garry wrote:
> commit 0b777eee88d712256ba8232a9429edb17c4f9ceb upstream
>
> In commit 376991db4b64 ("driver core: Postpone DMA tear-down until after
> devres release"), we changed the ordering of tearing down the device DMA
> ops and releasing all the device's resources; this was because the DMA ops
> should be maintained until we release the device's managed DMA memories.
>
> However, we have seen another crash on an arm64 system when a
> device driver probe fails:
>
> hisi_sas_v3_hw 0000:74:02.0: Adding to iommu group 2
> scsi host1: hisi_sas_v3_hw
> BUG: Bad page state in process swapper/0 pfn:313f5
> page:ffff7e0000c4fd40 count:1 mapcount:0
> mapping:0000000000000000 index:0x0
> flags: 0xfffe00000001000(reserved)
> raw: 0fffe00000001000 ffff7e0000c4fd48 ffff7e0000c4fd48
> 0000000000000000
> raw: 0000000000000000 0000000000000000 00000001ffffffff
> 0000000000000000
> page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
> bad because of flags: 0x1000(reserved)
> Modules linked in:
> CPU: 49 PID: 1 Comm: swapper/0 Not tainted
> 5.1.0-rc1-43081-g22d97fd-dirty #1433
> Hardware name: Huawei D06/D06, BIOS Hisilicon D06 UEFI
> RC0 - V1.12.01 01/29/2019
> Call trace:
> dump_backtrace+0x0/0x118
> show_stack+0x14/0x1c
> dump_stack+0xa4/0xc8
> bad_page+0xe4/0x13c
> free_pages_check_bad+0x4c/0xc0
> __free_pages_ok+0x30c/0x340
> __free_pages+0x30/0x44
> __dma_direct_free_pages+0x30/0x38
> dma_direct_free+0x24/0x38
> dma_free_attrs+0x9c/0xd8
> dmam_release+0x20/0x28
> release_nodes+0x17c/0x220
> devres_release_all+0x34/0x54
> really_probe+0xc4/0x2c8
> driver_probe_device+0x58/0xfc
> device_driver_attach+0x68/0x70
> __driver_attach+0x94/0xdc
> bus_for_each_dev+0x5c/0xb4
> driver_attach+0x20/0x28
> bus_add_driver+0x14c/0x200
> driver_register+0x6c/0x124
> __pci_register_driver+0x48/0x50
> sas_v3_pci_driver_init+0x20/0x28
> do_one_initcall+0x40/0x25c
> kernel_init_freeable+0x2b8/0x3c0
> kernel_init+0x10/0x100
> ret_from_fork+0x10/0x18
> Disabling lock debugging due to kernel taint
> BUG: Bad page state in process swapper/0 pfn:313f6
> page:ffff7e0000c4fd80 count:1 mapcount:0
> mapping:0000000000000000 index:0x0
> [ 89.322983] flags: 0xfffe00000001000(reserved)
> raw: 0fffe00000001000 ffff7e0000c4fd88 ffff7e0000c4fd88
> 0000000000000000
> raw: 0000000000000000 0000000000000000 00000001ffffffff
> 0000000000000000
>
> The crash occurs for the same reason.
>
> In this case, on the really_probe() failure path, we are still clearing
> the DMA ops prior to releasing the device's managed memories.
>
> This patch fixes this issue by reordering the DMA ops teardown and the
> call to devres_release_all() on the failure path.
>
> Reported-by: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>
> Tested-by: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>
> Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
> Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.12.x - 4.19.x
> Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> [jpg: backport to 4.19.x and earlier]
> Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
Now queued up everywhere, thanks for the backport.
greg k-h
