[PATCH] kdump: pass e820 reserved region to 2nd kernel via e820 table or setup_data

[WANG Chao]

e820 reserved region could be useful in 2nd kernel.

For example, PCI mmconf (extended mode) requires reserved region
otherwise it falls back to legacy mode. The following log is from Cliff
Wickman <cpw at sgi.com>:

 PCI: MMCONFIG for domain 1003 [bus 3f-3f] at [mem 0xff0ff00000-0xff0fffffff] (base 0xff0c000000)
 [Firmware Bug]: PCI: MMCONFIG at [mem 0x80000000-0x80cfffff] not reserved in ACPI motherboard resources
 PCI: not using MMCONFIG

PCI devices on segment 1 (>0) can't fall back to legacy mode, thus
kernel probing fails and device can't be found.

We don't pass reserved region because these regions could be too much
and eat up our very limited kernel command line resource in
memmap=exactmap case.

However now we use e820 map and setup_data to pass memory map to 2nd
kernel and the number of reserved regions should not be a problem any
more.

Signed-off-by: WANG Chao <chaowang at redhat.com>
---
 kexec/arch/i386/crashdump-x86.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/kexec/arch/i386/crashdump-x86.c b/kexec/arch/i386/crashdump-x86.c
index 4a1491b..321ed3d 100644
--- a/kexec/arch/i386/crashdump-x86.c
+++ b/kexec/arch/i386/crashdump-x86.c
@@ -300,6 +300,9 @@ static int get_crash_memory_ranges(struct memory_range **range, int *ranges,
 			type = RANGE_ACPI;
 		} else if(memcmp(str,"ACPI Non-volatile Storage\n",26) == 0 ) {
 			type = RANGE_ACPI_NVS;
+		} else if(memcmp(str,"reserved\n",9) == 0 ) {
+			type = RANGE_RANGE;
+		} else if (memcmp(str, "GART\n", 5) == 0) {
 		} else if (memcmp(str, "GART\n", 5) == 0) {
 			gart_start = start;
 			gart_end = end;
@@ -989,14 +992,15 @@ int load_crashdump_segments(struct kexec_info *info, char* mod_cmdline,
 	for (i = 0; i < CRASH_MAX_MEMORY_RANGES; i++) {
 		unsigned long start, end, size, type;
 		if ( !( mem_range[i].type == RANGE_ACPI
-			|| mem_range[i].type == RANGE_ACPI_NVS) )
+			|| mem_range[i].type == RANGE_ACPI_NVS
+			|| mem_range[i].type == RANGE_RESERVED))
 			continue;
 		start = mem_range[i].start;
 		end = mem_range[i].end;
 		type = mem_range[i].type;
 		size = end - start + 1;
 		add_memmap(memmap_p, &nr_memmap, start, size, type);
-		if (arch_options.pass_memmap_cmdline)
+		if (arch_options.pass_memmap_cmdline || type != RANGE_RESERVED)
 			cmdline_add_memmap_acpi(mod_cmdline, start, end);
 	}
 
-- 
1.9.0