From 26631da9bba6bcf000b4a87715cb3e8364afc373 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Tue, 10 Feb 2015 11:45:35 +0100 Subject: [PATCH 09/16] Restore atapi_dma flag across migration Message-id: <1423568736-19538-2-git-send-email-dgilbert@redhat.com> Patchwork-id: 63778 O-Subject: [RHEL-7.2 qemu-kvm PATCH 1/2] Restore atapi_dma flag across migration Bugzilla: 892258 RH-Acked-by: Juan Quintela RH-Acked-by: Laszlo Ersek RH-Acked-by: John Snow RH-Acked-by: Stefan Hajnoczi From: "Dr. David Alan Gilbert" If a migration happens just after the guest has kicked off an ATAPI command and kicked off DMA, we lose the atapi_dma flag, and the destination tries to complete the command as PIO rather than DMA. This upsets Linux; modern libata based kernels stumble and recover OK, older kernels end up passing bad data to userspace. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: John Snow Signed-off-by: Kevin Wolf (cherry picked from commit 819fa276311ce328a8e38ad9306c1093961b3f4b) Signed-off-by: Miroslav Rezanina --- hw/ide/core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/hw/ide/core.c b/hw/ide/core.c index 24a1708..9a22425 100644 --- a/hw/ide/core.c +++ b/hw/ide/core.c @@ -2283,6 +2283,7 @@ static int ide_drive_pio_post_load(void *opaque, int version_id) s->end_transfer_func = transfer_end_table[s->end_transfer_fn_idx]; s->data_ptr = s->io_buffer + s->cur_io_buffer_offset; s->data_end = s->data_ptr + s->cur_io_buffer_len; + s->atapi_dma = s->feature & 1; /* as per cmd_packet */ return 0; } -- 1.8.3.1