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[v3,1/5] Numachip: Fix 16-bit APIC ID truncation

Message ID 1414915813-2462-1-git-send-email-daniel@numascale.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show

Commit Message

Daniel J Blueman Nov. 2, 2014, 8:10 a.m. UTC 
Prevent 16-bit APIC IDs being truncated by using correct mask. This fixes
booting large systems, where the wrong core would receive the startup and
init IPIs, causing hanging.

Signed-off-by: Daniel J Blueman <daniel@numascale.com>
---
 arch/x86/kernel/apic/apic_numachip.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
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Patch

diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c
index 81d70ba..bd083c0 100644
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -40,7 +40,7 @@  static unsigned int get_apic_id(unsigned long x)
 	unsigned int id;
 
 	rdmsrl(MSR_FAM10H_NODE_ID, value);
-	id = ((x >> 24) & 0xffU) | ((value << 2) & 0x3f00U);
+	id = ((x >> 24) & 0xffU) | ((value << 2) & 0xff00U);
 
 	return id;
 }