Messages in this thread | | | Date | Wed, 3 Apr 2019 10:14:33 +0200 | From | Greg KH <> | Subject | Re: [PATCH] driver core: Postpone DMA tear-down until after devres release for probe failure |
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On Wed, Apr 03, 2019 at 09:02:36AM +0100, John Garry wrote: > On 28/03/2019 10:08, John Garry wrote: > > 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. > > > > Hi all, > > A friendly reminder on this patch... I didn't see any update. > > I thought that it had some importance. > > Thanks, > John > > > 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@hisilicon.com> > > Tested-by: Xiang Chen <chenxiang66@hisilicon.com> > > Signed-off-by: John Garry <john.garry@huawei.com>
So does this "fix" 376991db4b64? If so, should this be added to the patch and also backported to the stable trees?
thanks,
greg k-h
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