From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Date: Fri, 17 Aug 2012 13:35:31 +0000 (-0400)
Subject: xen/mmu: If the revector fails, don't attempt to revector anything else.
X-Git-Tag: v2.6.39-400.9.0~418^2^2
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=dda7f430fd5e2c55d8df3a8629fbe79b5b5954ad;p=users%2Fjedix%2Flinux-maple.git

xen/mmu: If the revector fails, don't attempt to revector anything else.

If the P2M revectoring would fail, we would try to continue on by
cleaning the PMD for L1 (PTE) page-tables. The xen_cleanhighmap
is greedy and erases the PMD on both boundaries. Since the P2M
array can share the PMD, we would wipe out part of the __ka
that is still used in the P2M tree to point to P2M leafs.

This fixes it by bypassing the revectoring and continuing on.
If the revector fails, a nice WARN is printed so we can still
troubleshoot this.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index f610c2b00f3b..af2c7e6258fc 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1250,7 +1250,8 @@ static void __init xen_pagetable_setup_done(pgd_t *base)
 			memblock_x86_free_range(__pa(xen_start_info->mfn_list), __pa(xen_start_info->mfn_list) + size);
 			/* And revector! Bye bye old array */
 			xen_start_info->mfn_list = new_mfn_list;
-		}
+		} else
+			goto skip;
 	}
 	/* At this stage, cleanup_highmap has already cleaned __ka space
 	 * from _brk_limit way up to the max_pfn_mapped (which is the end of
@@ -1271,6 +1272,7 @@ static void __init xen_pagetable_setup_done(pgd_t *base)
 	 * anything at this stage. */
 	xen_cleanhighmap(MODULES_VADDR, roundup(MODULES_VADDR, PUD_SIZE) - 1);
 #endif
+skip:
 #endif
 	xen_post_allocator_init();
 }