diff options
author | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2011-01-27 10:13:25 -0500 |
---|---|---|
committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2011-01-27 10:49:35 -0500 |
commit | 7cb31b752c71e0bd405c1139e1907c3335877dff (patch) | |
tree | fb867bd74a89ddff24075907080faa41b33797f2 /arch/x86 | |
parent | cf04d120d9413de581437cf9a29f138ec1178f65 (diff) |
xen/e820: Guard against E820_RAM not having page-aligned size or start.
Under Dell Inspiron 1525, and Intel SandyBridge SDP's the
BIOS e820 RAM is not page-aligned:
[ 0.000000] Xen: 0000000000100000 - 00000000df66d800 (usable)
We were not handling that and ended up setting up a pagetable
that included up to df66e000 with the disastrous effect that when
memset(NODE_DATA(nodeid), 0, sizeof(pg_data_t));
tried to clear the page it would crash at the 2K mark.
Initially reported by Michael Young @
http://lists.xensource.com/archives/html/xen-devel/2011-01/msg00108.html
The fix is to page-align the size and also take into consideration
the start of the E820 (in case that is not page-aligned either). This
fixes the bootup failure on those affected machines.
This patch is a rework of the Micheal A Young initial patch and
considers the case if the start is not page-aligned.
Reported-by: Michael A Young <m.a.young@durham.ac.uk>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Michael A Young <m.a.young@durham.ac.uk>
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/xen/setup.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index b5a7f928234b..75bdf2ab3d7c 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c | |||
@@ -179,8 +179,13 @@ char * __init xen_memory_setup(void) | |||
179 | e820.nr_map = 0; | 179 | e820.nr_map = 0; |
180 | xen_extra_mem_start = mem_end; | 180 | xen_extra_mem_start = mem_end; |
181 | for (i = 0; i < memmap.nr_entries; i++) { | 181 | for (i = 0; i < memmap.nr_entries; i++) { |
182 | unsigned long long end = map[i].addr + map[i].size; | 182 | unsigned long long end; |
183 | 183 | ||
184 | /* Guard against non-page aligned E820 entries. */ | ||
185 | if (map[i].type == E820_RAM) | ||
186 | map[i].size -= (map[i].size + map[i].addr) % PAGE_SIZE; | ||
187 | |||
188 | end = map[i].addr + map[i].size; | ||
184 | if (map[i].type == E820_RAM && end > mem_end) { | 189 | if (map[i].type == E820_RAM && end > mem_end) { |
185 | /* RAM off the end - may be partially included */ | 190 | /* RAM off the end - may be partially included */ |
186 | u64 delta = min(map[i].size, end - mem_end); | 191 | u64 delta = min(map[i].size, end - mem_end); |