From 8d4dd919b46ed982da6ef6bf6fcec454cd7a5b1b Mon Sep 17 00:00:00 2001 From: Yinghai Lu 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 Cc: Andrew Morton LKML-Reference: <49AE4901.3090801@kernel.org> Signed-off-by: Ingo Molnar Reported-and-tested-by: Kevin O'Connor --- 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 37cb1bda1baf..ae9060cb4481 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