Re: [coreboot] [PATCH] x86: ioremap mptable -v2

[Yinghai Lu]

Ingo Molnar wrote:
> Yinghai Lu  wrote:
> > Impact: fix boot with mptable above max_low_mapped
> >
> > try to use early_ioremap it.
> >
> > v2: also get the exact size for reserve_bootmem in case we got big size than 4k
> >
> > Signed-off-by: Yinghai Lu 
> > Reported-and-tested-by: Kevin O'Connor
> >
> > arch/x86/kernel/mpparse.c |   20 ++++++++++++++++++--
> >  1 file changed, 18 insertions(+), 2 deletions(-)
> > Index: linux-2.6/arch/x86/kernel/mpparse.c
> >
> > --- linux-2.6.orig/arch/x86/kernel/mpparse.c
> > +++ linux-2.6/arch/x86/kernel/mpparse.c
> > @@ -611,12 +611,20 @@ static void __init __get_smp_config(unsi
> >    	construct_default_ISA_mptable(mpf->feature1);
> >
> > } else if (mpf->physptr) {
> > struct mpc_table *mpc;
> > unsigned long size;
> >
> > mpc = early_ioremap(mpf->physptr, PAGE_SIZE);
> > size = mpc->length;
> > apic_printk(APIC_VERBOSE, "  mpc: %lx-%lx\n", (unsigned long)mpf->physptr,
> > 	 mpf->physptr + size);
> > early_iounmap(mpc, PAGE_SIZE);
> > mpc = early_ioremap(mpf->physptr, size);
>
> no objections, but this bit of __get_smp_config() needs to be 
> done cleaner - the whole mpf->physptr != 0 bit should probably 
> go into a helper function.

please check

[PATCH] x86: ioremap mptable -v3

Impact: fix boot with mptable above max_low_mapped

try to use early_ioremap it.

v2: also get the exact size for reserve_bootmem in case we got big size than 4k
V3: according to Ingo, seperate get_mpc_size()

Signed-off-by: Yinghai Lu 
Reported-and-tested-by: Kevin O'Connor

---
 arch/x86/kernel/mpparse.c |   24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

Index: linux-2.6/arch/x86/kernel/mpparse.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/mpparse.c
+++ linux-2.6/arch/x86/kernel/mpparse.c
@@ -558,6 +558,19 @@ static inline void __init construct_defa

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(unsi
    	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
@@ -624,9 +641,12 @@ static void __init __get_smp_config(unsi
    		       "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;
 #ifdef CONFIG_X86_IO_APIC
@@ -700,7 +720,7 @@ static int __init smp_scan_config(unsign
    		reserve_bootmem_generic(virt_to_phys(mpf), PAGE_SIZE,
    				BOOTMEM_DEFAULT);
    		if (mpf->physptr) {
-				unsigned long size = PAGE_SIZE;
+				unsigned long size = get_mpc_size(mpf->physptr);
 #ifdef CONFIG_X86_32
    			/*
    			 * We cannot access to MPC table to compute