From 8d4dd919b46ed982da6ef6bf6fcec454cd7a5b1b Mon Sep 17 00:00:00 2001
From: Yinghai Lu <yinghai@kernel.org>
Date: Wed, 4 Mar 2009 01:25:21 -0800
Subject: [PATCH] x86: ioremap mptable
Impact: fix boot with mptable above max_low_mapped
Try to use early_ioremap() to map MPC to make sure it works even it is
at the end of ram.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <49AE4901.3090801@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reported-and-tested-by: Kevin O'Connor <kevin@koconnor.net>
---
arch/x86/kernel/mpparse.c | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
index 37cb1bda1ba..ae9060cb448 100644
--- a/arch/x86/kernel/mpparse.c
+++ b/arch/x86/kernel/mpparse.c
@@ -558,6 +558,19 @@ static inline void __init construct_default_ISA_mptable(int mpc_default_type)
static struct mpf_intel *mpf_found;
+static unsigned long __init get_mpc_size(unsigned long physptr)
+{
+ struct mpc_table *mpc;
+ unsigned long size;
+
+ mpc = early_ioremap(physptr, PAGE_SIZE);
+ size = mpc->length;
+ early_iounmap(mpc, PAGE_SIZE);
+ apic_printk(APIC_VERBOSE, " mpc: %lx-%lx\n", physptr, physptr + size);
+
+ return size;
+}
+
/*
* Scan the memory blocks for an SMP configuration block.
*/
@@ -611,12 +624,16 @@ static void __init __get_smp_config(unsigned int early)
construct_default_ISA_mptable(mpf->feature1);
} else if (mpf->physptr) {
+ struct mpc_table *mpc;
+ unsigned long size;
+ size = get_mpc_size(mpf->physptr);
+ mpc = early_ioremap(mpf->physptr, size);
/*
* Read the physical hardware table. Anything here will
* override the defaults.
*/
- if (!smp_read_mpc(phys_to_virt(mpf->physptr), early)) {
+ if (!smp_read_mpc(mpc, early)) {
#ifdef CONFIG_X86_LOCAL_APIC
smp_found_config = 0;
#endif
@@ -624,8 +641,10 @@ static void __init __get_smp_config(unsigned int early)
"BIOS bug, MP table errors detected!...\n");
printk(KERN_ERR "... disabling SMP support. "
"(tell your hw vendor)\n");
+ early_iounmap(mpc, size);
return;
}
+ early_iounmap(mpc, size);
if (early)
return;
--
2.20.1