From: Julien Grall Date: Wed, 15 Nov 2017 19:34:14 +0000 (+0000) Subject: xen/arm: p2m: Add more debug in get_page_from_gva X-Git-Tag: archive/raspbian/4.11.1-1+rpi1~1^2~66^2~1028 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=ca4b2e52a894845f26fc5b784f465e31c4cef90b;p=xen.git xen/arm: p2m: Add more debug in get_page_from_gva The function get_page_from_gva is used by copy_*_guest helpers to translate a guest virtual address to a machine physical address and take reference on the page. There are a couple of errors paths that will return the same value making it difficult to know the exact error. Add more debug in each error patch only for debug-build. This should help narrowing down the intermittent failure with the hypercall GNTTABOP_copy (see [1]). [1] https://lists.xen.org/archives/html/xen-devel/2017-11/msg00942.html Signed-off-by: Julien Grall Acked-by: Stefano Stabellini Signed-off-by: Stefano Stabellini --- diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c index f6b3d8e421..417609ede2 100644 --- a/xen/arch/arm/p2m.c +++ b/xen/arch/arm/p2m.c @@ -1428,16 +1428,29 @@ struct page_info *get_page_from_gva(struct vcpu *v, vaddr_t va, par = gvirt_to_maddr(va, &maddr, flags); if ( par ) + { + dprintk(XENLOG_G_DEBUG, + "%pv: gvirt_to_maddr failed va=%#"PRIvaddr" flags=0x%lx par=%#"PRIx64"\n", + v, va, flags, par); goto err; + } if ( !mfn_valid(maddr_to_mfn(maddr)) ) + { + dprintk(XENLOG_G_DEBUG, "%pv: Invalid MFN %#"PRI_mfn"\n", + v, mfn_x(maddr_to_mfn(maddr))); goto err; + } page = mfn_to_page(maddr_to_mfn(maddr)); ASSERT(page); if ( unlikely(!get_page(page, d)) ) + { + dprintk(XENLOG_G_DEBUG, "%pv: Failing to acquire the MFN %#"PRI_mfn"\n", + v, mfn_x(maddr_to_mfn(maddr))); page = NULL; + } err: if ( !page && p2m->mem_access_enabled )