svn commit: r280434 - head/sys/x86/iommu

[Konstantin Belousov]

Author: kib
Date: Tue Mar 24 12:46:21 2015
New Revision: 280434
URL: https://svnweb.freebsd.org/changeset/base/280434

Log:
  Assert that the mapping loop makes progress.
  
  Sponsored by:	The FreeBSD Foundation
  MFC after:	1 week

Modified:
  head/sys/x86/iommu/intel_idpgtbl.c

Modified: head/sys/x86/iommu/intel_idpgtbl.c
==============================================================================
--- head/sys/x86/iommu/intel_idpgtbl.c	Tue Mar 24 11:33:34 2015	(r280433)
+++ head/sys/x86/iommu/intel_idpgtbl.c	Tue Mar 24 12:46:21 2015	(r280434)
@@ -465,6 +465,7 @@ ctx_map_buf_locked(struct dmar_ctx *ctx,
 		KASSERT(size >= pg_sz,
 		    ("mapping loop overflow %p %jx %jx %jx", ctx,
 		    (uintmax_t)base, (uintmax_t)size, (uintmax_t)pg_sz));
+		KASSERT(pg_sz > 0, ("pg_sz 0 lvl %d", lvl));
 		pte = ctx_pgtbl_map_pte(ctx, base, lvl, flags, &idx, &sf);
 		if (pte == NULL) {
 			KASSERT((flags & DMAR_PGF_WAITOK) == 0,