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: hpet: Work around hardware stupidity
  x86, build: Disable -fPIE when compiling with CONFIG_CC_STACKPROTECTOR=y
  x86, cpufeature: Suppress compiler warning with gcc 3.x
  x86, UV: Fix initialization of max_pnode

3 files changed, 20 insertions, 35 deletions

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 7b598b84c902..f744f54cb248 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -698,9 +698,11 @@ void __init uv_system_init(void)
 		for (j = 0; j < 64; j++) {
 			if (!test_bit(j, &present))
 				continue;
-			uv_blade_info[blade].pnode = (i * 64 + j);
+			pnode = (i * 64 + j);
+			uv_blade_info[blade].pnode = pnode;
 			uv_blade_info[blade].nr_possible_cpus = 0;
 			uv_blade_info[blade].nr_online_cpus = 0;
+			max_pnode = max(pnode, max_pnode);
 			blade++;
 		}
 	}
@@ -738,7 +740,6 @@ void __init uv_system_init(void)
 		uv_cpu_hub_info(cpu)->scir.offset = uv_scir_offset(apicid);
 		uv_node_to_blade[nid] = blade;
 		uv_cpu_to_blade[cpu] = blade;
-		max_pnode = max(pnode, max_pnode);
 	}
 
 	/* Add blade/pnode info for nodes without cpus */
@@ -750,7 +751,6 @@ void __init uv_system_init(void)
 		pnode = (paddr >> m_val) & pnode_mask;
 		blade = boot_pnode_to_blade(pnode);
 		uv_node_to_blade[nid] = blade;
-		max_pnode = max(pnode, max_pnode);
 	}
 
 	map_gru_high(max_pnode);
diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c
index e5cc7e82e60d..ebdb85cf2686 100644
--- a/arch/x86/kernel/early-quirks.c
+++ b/arch/x86/kernel/early-quirks.c
@@ -18,7 +18,6 @@
 #include <asm/apic.h>
 #include <asm/iommu.h>
 #include <asm/gart.h>
-#include <asm/hpet.h>
 
 static void __init fix_hypertransport_config(int num, int slot, int func)
 {
@@ -192,21 +191,6 @@ static void __init ati_bugs_contd(int num, int slot, int func)
 }
 #endif
 
-/*
- * Force the read back of the CMP register in hpet_next_event()
- * to work around the problem that the CMP register write seems to be
- * delayed. See hpet_next_event() for details.
- *
- * We do this on all SMBUS incarnations for now until we have more
- * information about the affected chipsets.
- */
-static void __init ati_hpet_bugs(int num, int slot, int func)
-{
-#ifdef CONFIG_HPET_TIMER
-	hpet_readback_cmp = 1;
-#endif
-}
-
 #define QFLAG_APPLY_ONCE 	0x1
 #define QFLAG_APPLIED		0x2
 #define QFLAG_DONE		(QFLAG_APPLY_ONCE|QFLAG_APPLIED)
@@ -236,8 +220,6 @@ static struct chipset early_qrk[] __initdata = {
 	  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs },
 	{ PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS,
 	  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs_contd },
-	{ PCI_VENDOR_ID_ATI, PCI_ANY_ID,
-	  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_hpet_bugs },
 	{}
 };
 
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index 351f9c0fea1f..410fdb3f1939 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -35,7 +35,6 @@
 unsigned long				hpet_address;
 u8					hpet_blockid; /* OS timer block num */
 u8					hpet_msi_disable;
-u8					hpet_readback_cmp;
 
 #ifdef CONFIG_PCI_MSI
 static unsigned long			hpet_num_timers;
@@ -395,23 +394,27 @@ static int hpet_next_event(unsigned long delta,
 	 * at that point and we would wait for the next hpet interrupt
 	 * forever. We found out that reading the CMP register back
 	 * forces the transfer so we can rely on the comparison with
-	 * the counter register below.
+	 * the counter register below. If the read back from the
+	 * compare register does not match the value we programmed
+	 * then we might have a real hardware problem. We can not do
+	 * much about it here, but at least alert the user/admin with
+	 * a prominent warning.
 	 *
-	 * That works fine on those ATI chipsets, but on newer Intel
-	 * chipsets (ICH9...) this triggers due to an erratum: Reading
-	 * the comparator immediately following a write is returning
-	 * the old value.
+	 * An erratum on some chipsets (ICH9,..), results in
+	 * comparator read immediately following a write returning old
+	 * value. Workaround for this is to read this value second
+	 * time, when first read returns old value.
 	 *
-	 * We restrict the read back to the affected ATI chipsets (set
-	 * by quirks) and also run it with hpet=verbose for debugging
-	 * purposes.
+	 * In fact the write to the comparator register is delayed up
+	 * to two HPET cycles so the workaround we tried to restrict
+	 * the readback to those known to be borked ATI chipsets
+	 * failed miserably. So we give up on optimizations forever
+	 * and penalize all HPET incarnations unconditionally.
 	 */
-	if (hpet_readback_cmp || hpet_verbose) {
-		u32 cmp = hpet_readl(HPET_Tn_CMP(timer));
-
-		if (cmp != cnt)
+	if (unlikely((u32)hpet_readl(HPET_Tn_CMP(timer)) != cnt)) {
+		if (hpet_readl(HPET_Tn_CMP(timer)) != cnt)
 			printk_once(KERN_WARNING
-			    "hpet: compare register read back failed.\n");
+				"hpet: compare register read back failed.\n");
 	}
 
 	return (s32)(hpet_readl(HPET_COUNTER) - cnt) >= 0 ? -ETIME : 0;