From: Shameer Kolothum Date: Mon, 20 Nov 2023 09:14:06 +0000 (+0000) Subject: hisi_acc_vfio_pci: Update migration data pointer correctly on saving/resume X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=be12ad45e15b5ee0e2526a50266ba1d295d26a88;p=linux.git hisi_acc_vfio_pci: Update migration data pointer correctly on saving/resume When the optional PRE_COPY support was added to speed up the device compatibility check, it failed to update the saving/resuming data pointers based on the fd offset. This results in migration data corruption and when the device gets started on the destination the following error is reported in some cases, [ 478.907684] arm-smmu-v3 arm-smmu-v3.2.auto: event 0x10 received: [ 478.913691] arm-smmu-v3 arm-smmu-v3.2.auto: 0x0000310200000010 [ 478.919603] arm-smmu-v3 arm-smmu-v3.2.auto: 0x000002088000007f [ 478.925515] arm-smmu-v3 arm-smmu-v3.2.auto: 0x0000000000000000 [ 478.931425] arm-smmu-v3 arm-smmu-v3.2.auto: 0x0000000000000000 [ 478.947552] hisi_zip 0000:31:00.0: qm_axi_rresp [error status=0x1] found [ 478.955930] hisi_zip 0000:31:00.0: qm_db_timeout [error status=0x400] found [ 478.955944] hisi_zip 0000:31:00.0: qm sq doorbell timeout in function 2 Fixes: d9a871e4a143 ("hisi_acc_vfio_pci: Introduce support for PRE_COPY state transitions") Signed-off-by: Shameer Kolothum Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20231120091406.780-1-shameerali.kolothum.thodi@huawei.com Signed-off-by: Alex Williamson --- diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c index b2f9778c8366e..4d27465c8f1a8 100644 --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c @@ -694,6 +694,7 @@ static ssize_t hisi_acc_vf_resume_write(struct file *filp, const char __user *bu size_t len, loff_t *pos) { struct hisi_acc_vf_migration_file *migf = filp->private_data; + u8 *vf_data = (u8 *)&migf->vf_data; loff_t requested_length; ssize_t done = 0; int ret; @@ -715,7 +716,7 @@ static ssize_t hisi_acc_vf_resume_write(struct file *filp, const char __user *bu goto out_unlock; } - ret = copy_from_user(&migf->vf_data, buf, len); + ret = copy_from_user(vf_data + *pos, buf, len); if (ret) { done = -EFAULT; goto out_unlock; @@ -835,7 +836,9 @@ static ssize_t hisi_acc_vf_save_read(struct file *filp, char __user *buf, size_t len = min_t(size_t, migf->total_length - *pos, len); if (len) { - ret = copy_to_user(buf, &migf->vf_data, len); + u8 *vf_data = (u8 *)&migf->vf_data; + + ret = copy_to_user(buf, vf_data + *pos, len); if (ret) { done = -EFAULT; goto out_unlock;