Merge branch 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: mask extended topology info in cpuid
xen/hvc: make sure console output is always emitted, with explicit polling
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 23a4d80..dfbf70e 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -178,6 +178,7 @@
static void xen_cpuid(unsigned int *ax, unsigned int *bx,
unsigned int *cx, unsigned int *dx)
{
+ unsigned maskebx = ~0;
unsigned maskecx = ~0;
unsigned maskedx = ~0;
@@ -185,9 +186,16 @@
* Mask out inconvenient features, to try and disable as many
* unsupported kernel subsystems as possible.
*/
- if (*ax == 1) {
+ switch (*ax) {
+ case 1:
maskecx = cpuid_leaf1_ecx_mask;
maskedx = cpuid_leaf1_edx_mask;
+ break;
+
+ case 0xb:
+ /* Suppress extended topology stuff */
+ maskebx = 0;
+ break;
}
asm(XEN_EMULATE_PREFIX "cpuid"
@@ -197,6 +205,7 @@
"=d" (*dx)
: "0" (*ax), "2" (*cx));
+ *bx &= maskebx;
*cx &= maskecx;
*dx &= maskedx;
}
diff --git a/drivers/char/hvc_xen.c b/drivers/char/hvc_xen.c
index eba999f..a6ee32b 100644
--- a/drivers/char/hvc_xen.c
+++ b/drivers/char/hvc_xen.c
@@ -55,7 +55,7 @@
notify_remote_via_evtchn(xen_start_info->console.domU.evtchn);
}
-static int write_console(uint32_t vtermno, const char *data, int len)
+static int __write_console(const char *data, int len)
{
struct xencons_interface *intf = xencons_interface();
XENCONS_RING_IDX cons, prod;
@@ -76,6 +76,29 @@
return sent;
}
+static int write_console(uint32_t vtermno, const char *data, int len)
+{
+ int ret = len;
+
+ /*
+ * Make sure the whole buffer is emitted, polling if
+ * necessary. We don't ever want to rely on the hvc daemon
+ * because the most interesting console output is when the
+ * kernel is crippled.
+ */
+ while (len) {
+ int sent = __write_console(data, len);
+
+ data += sent;
+ len -= sent;
+
+ if (unlikely(len))
+ HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
+ }
+
+ return ret;
+}
+
static int read_console(uint32_t vtermno, char *buf, int len)
{
struct xencons_interface *intf = xencons_interface();