Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, geode: add a VSA2 ID for General Software
  x86: use BOOTMEM_EXCLUSIVE on 32-bit
  x86, 32-bit: fix boot failure on TSC-less processors
  x86: fix NULL pointer deref in __switch_to
  x86: set PAE PHYSICAL_MASK_SHIFT to 44 bits.

5 files changed, 22 insertions, 13 deletions

diff --git a/arch/x86/kernel/geode_32.c b/arch/x86/kernel/geode_32.c
index e8edd63..9b08e85 100644
--- a/arch/x86/kernel/geode_32.c
+++ b/arch/x86/kernel/geode_32.c
@@ -166,6 +166,8 @@ int geode_has_vsa2(void)
 	static int has_vsa2 = -1;
 
 	if (has_vsa2 == -1) {
+		u16 val;
+
 		/*
 		 * The VSA has virtual registers that we can query for a
 		 * signature.
@@ -173,7 +175,8 @@ int geode_has_vsa2(void)
 		outw(VSA_VR_UNLOCK, VSA_VRC_INDEX);
 		outw(VSA_VR_SIGNATURE, VSA_VRC_INDEX);
 
-		has_vsa2 = (inw(VSA_VRC_DATA) == VSA_SIG);
+		val = inw(VSA_VRC_DATA);
+		has_vsa2 = (val == AMD_VSA_SIG || val == GSW_VSA_SIG);
 	}
 
 	return has_vsa2;
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 6d54833..e2db9ac 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -333,6 +333,7 @@ void flush_thread(void)
 	/*
 	 * Forget coprocessor state..
 	 */
+	tsk->fpu_counter = 0;
 	clear_fpu(tsk);
 	clear_used_math();
 }
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index ac54ff5..c6eb5c9 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -294,6 +294,7 @@ void flush_thread(void)
 	/*
 	 * Forget coprocessor state..
 	 */
+	tsk->fpu_counter = 0;
 	clear_fpu(tsk);
 	clear_used_math();
 }
diff --git a/arch/x86/kernel/setup_32.c b/arch/x86/kernel/setup_32.c
index 2c5f8b2..5a2f8e0 100644
--- a/arch/x86/kernel/setup_32.c
+++ b/arch/x86/kernel/setup_32.c
@@ -532,10 +532,16 @@ static void __init reserve_crashkernel(void)
 					(unsigned long)(crash_size >> 20),
 					(unsigned long)(crash_base >> 20),
 					(unsigned long)(total_mem >> 20));
+
+			if (reserve_bootmem(crash_base, crash_size,
+					BOOTMEM_EXCLUSIVE) < 0) {
+				printk(KERN_INFO "crashkernel reservation "
+					"failed - memory is in use\n");
+				return;
+			}
+
 			crashk_res.start = crash_base;
 			crashk_res.end   = crash_base + crash_size - 1;
-			reserve_bootmem(crash_base, crash_size,
-					BOOTMEM_DEFAULT);
 		} else
 			printk(KERN_INFO "crashkernel reservation failed - "
 					"you have to specify a base address\n");
diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c
index 068759d..65b7063 100644
--- a/arch/x86/kernel/tsc_32.c
+++ b/arch/x86/kernel/tsc_32.c
@@ -14,7 +14,10 @@
 
 #include "mach_timer.h"
 
-static int tsc_disabled;
+/* native_sched_clock() is called before tsc_init(), so
+   we must start with the TSC soft disabled to prevent
+   erroneous rdtsc usage on !cpu_has_tsc processors */
+static int tsc_disabled = -1;
 
 /*
  * On some systems the TSC frequency does not
@@ -402,25 +405,20 @@ void __init tsc_init(void)
 {
 	int cpu;
 
-	if (!cpu_has_tsc || tsc_disabled) {
-		/* Disable the TSC in case of !cpu_has_tsc */
-		tsc_disabled = 1;
+	if (!cpu_has_tsc || tsc_disabled > 0)
 		return;
-	}
 
 	cpu_khz = calculate_cpu_khz();
 	tsc_khz = cpu_khz;
 
 	if (!cpu_khz) {
 		mark_tsc_unstable("could not calculate TSC khz");
-		/*
-		 * We need to disable the TSC completely in this case
-		 * to prevent sched_clock() from using it.
-		 */
-		tsc_disabled = 1;
 		return;
 	}
 
+	/* now allow native_sched_clock() to use rdtsc */
+	tsc_disabled = 0;
+
 	printk("Detected %lu.%03lu MHz processor.\n",
 				(unsigned long)cpu_khz / 1000,
 				(unsigned long)cpu_khz % 1000);