From 69e8f430e243d657c2053f097efebc2e2cd559f0 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Wed, 25 Jan 2012 00:13:20 -0500 Subject: [PATCH] xen/granttable: Disable grant v2 for HVM domains. As proper scaffolding for supporting error status is not yet implemented. BUG: unable to handle kernel NULL pointer dereference at 0000000000000400 IP: [] gnttab_end_foreign_access_ref_v2+0x29/0x40 PGD 32aa3067 PUD 32a87067 PMD 0 Oops: 0000 [#1] PREEMPT SMP CPU 0 Modules linked in: sg sr_mod cdrom ata_generic ata_piix libata scsi_mod xen_blkfront xen_netfront fb_sys_fops sysimgblt sysfillrect syscopyarea xen_kbdfront cmd Pid: 2307, comm: ip Not tainted 3.3.0-rc1 #1 Xen HVM domU RIP: 0010:[] [] gnttab_end_foreign_access_ref_v2+0x29/0x40 RSP: 0018:ffff88003be03d38 EFLAGS: 00010206 RAX: 0000000000000000 RBX: ffff880033210640 RCX: 0000000000000040 RDX: 0000000000002000 RSI: 0000000000000000 RDI: 0000000000000200 RBP: ffff88003be03d38 R08: 0000000000000101 R09: 0000000000000000 R10: dead000000100100 R11: 0000000000000000 R12: ffff88003be03e48 R13: 0000000000000001 R14: ffff880039461c00 R15: 0000000000000200 FS: 00007fb1f84ec700(0000) GS:ffff88003be00000(0000) knlGS:0000000000000000 ... Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/grant-table.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 1cd94daa71db..b4d4eac761db 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -948,9 +948,12 @@ static void gnttab_request_version(void) int rc; struct gnttab_set_version gsv; - gsv.version = 2; + if (xen_hvm_domain()) + gsv.version = 1; + else + gsv.version = 2; rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1); - if (rc == 0) { + if (rc == 0 && gsv.version == 2) { grant_table_version = 2; gnttab_interface = &gnttab_v2_ops; } else if (grant_table_version == 2) { -- 2.30.2