lkml.org 
[lkml]   [2021]   [Oct]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] PCI/MSI: fix page fault when msi_populate_sysfs() failed
From
Date

在 2021/10/11 16:52, Barry Song 写道:
> On Mon, Oct 11, 2021 at 9:24 PM Wang Hai <wanghai38@huawei.com> wrote:
>> I got a page fault report when doing fault injection test:
>>
>> BUG: unable to handle page fault for address: fffffffffffffff4
>> ...
>> RIP: 0010:sysfs_remove_groups+0x25/0x60
>> ...
>> Call Trace:
>> msi_destroy_sysfs+0x30/0xa0
>> free_msi_irqs+0x11d/0x1b0
>> __pci_enable_msix_range+0x67f/0x760
>> pci_alloc_irq_vectors_affinity+0xe7/0x170
>> vp_find_vqs_msix+0x129/0x560
>> vp_find_vqs+0x52/0x230
>> vp_modern_find_vqs+0x47/0xb0
>> p9_virtio_probe+0xa1/0x460 [9pnet_virtio]
>> virtio_dev_probe+0x1ed/0x2e0
>> really_probe+0x1c7/0x400
>> __driver_probe_device+0xa4/0x120
>> driver_probe_device+0x32/0xe0
>> __driver_attach+0xbf/0x130
>> bus_for_each_dev+0xbb/0x110
>> driver_attach+0x27/0x30
>> bus_add_driver+0x1d9/0x270
>> driver_register+0xa9/0x180
>> register_virtio_driver+0x31/0x50
>> p9_virtio_init+0x3c/0x1000 [9pnet_virtio]
>> do_one_initcall+0x7b/0x380
>> do_init_module+0x5f/0x21e
>> load_module+0x265c/0x2c60
>> __do_sys_finit_module+0xb0/0xf0
>> __x64_sys_finit_module+0x1a/0x20
>> do_syscall_64+0x34/0xb0
>> entry_SYSCALL_64_after_hwframe+0x44/0xae
>>
>> When populating msi_irqs sysfs failed in msi_capability_init() or
>> msix_capability_init(), dev->msi_irq_groups will point to ERR_PTR(...).
>> This will cause a page fault when destroying the wrong
>> dev->msi_irq_groups in free_msi_irqs().
>>
>> Fix this by setting dev->msi_irq_groups to NULL when msi_populate_sysfs()
>> failed.
>>
>> Fixes: 2f170814bdd2 ("genirq/msi: Move MSI sysfs handling from PCI to MSI core")
>> Reported-by: Hulk Robot <hulkci@huawei.com>
>> Signed-off-by: Wang Hai <wanghai38@huawei.com>
> Acked-by: Barry Song <song.bao.hua@hisilicon.com>
>
>> ---
>> drivers/pci/msi.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
>> index 0099a00af361..6f75db9f3be7 100644
>> --- a/drivers/pci/msi.c
>> +++ b/drivers/pci/msi.c
>> @@ -561,6 +561,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec,
>> dev->msi_irq_groups = msi_populate_sysfs(&dev->dev);
>> if (IS_ERR(dev->msi_irq_groups)) {
>> ret = PTR_ERR(dev->msi_irq_groups);
>> + dev->msi_irq_groups = NULL;
>> goto err;
>> }
>>
>> @@ -733,6 +734,7 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
>> dev->msi_irq_groups = msi_populate_sysfs(&dev->dev);
>> if (IS_ERR(dev->msi_irq_groups)) {
>> ret = PTR_ERR(dev->msi_irq_groups);
>> + dev->msi_irq_groups = NULL;
> Can you define a temp variable and assign it to dev->msi_irq_groups if
> the temp variable
> is not PTR_ERR?
Of course, I will send a v2 patch.
>
>> goto out_free;
>> }
>>
>> --
>> 2.17.1
>>
> Thanks
> Barry
> .
>
--
Wang Hai

\
 
 \ /
  Last update: 2021-10-11 11:15    [W:0.070 / U:0.372 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site