From 5c0e6f035df983210e4d22213aed624ced502d3d Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Thu, 12 Mar 2009 13:07:23 +0000 Subject: x86: fix code paths used by update_mptable Impact: fix crashes under Xen due to unrobust e820 code find_e820_area_size() must return a properly distinguishable and out-of-bounds value when it fails, and -1UL does not meet that criteria on i386/PAE. Additionally, callers of the function must check against that value. early_reserve_e820() should be prepared for the region found to be outside of the addressable range on 32-bits. e820_update_range_map() should not blindly update e820, but should do all it work on the map it got a pointer passed for (which in 50% of the cases is &e820_saved). It must also not call e820_add_region(), as that again acts on e820 unconditionally. The issues were found when trying to make this option work in our Xen kernel (i.e. where some of the silent assumptions made in the code would not hold). Signed-off-by: Jan Beulich LKML-Reference: <49B9171B.76E4.0078.0@novell.com> Signed-off-by: Ingo Molnar --- arch/x86/kernel/check.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel/check.c') diff --git a/arch/x86/kernel/check.c b/arch/x86/kernel/check.c index 2ac0ab71412..b617b1164f1 100644 --- a/arch/x86/kernel/check.c +++ b/arch/x86/kernel/check.c @@ -83,7 +83,7 @@ void __init setup_bios_corruption_check(void) u64 size; addr = find_e820_area_size(addr, &size, PAGE_SIZE); - if (addr == 0) + if (!(addr + 1)) break; if ((addr + size) > corruption_check_size) -- cgit v1.2.3 From 6d7942dc2a70a7e74c352107b150265602671588 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 14 Mar 2009 14:32:41 -0700 Subject: x86: fix 64k corruption-check Impact: fix boot crash Need to exit early if the addr is far above 64k. The crash got exposed by: 78a8b35: x86: make e820_update_range() handle small range update Signed-off-by: Yinghai Lu Cc: LKML-Reference: <49BC2279.2030101@kernel.org> Signed-off-by: Ingo Molnar --- arch/x86/kernel/check.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel/check.c') diff --git a/arch/x86/kernel/check.c b/arch/x86/kernel/check.c index b617b1164f1..fc999e6fc46 100644 --- a/arch/x86/kernel/check.c +++ b/arch/x86/kernel/check.c @@ -86,12 +86,12 @@ void __init setup_bios_corruption_check(void) if (!(addr + 1)) break; + if (addr >= corruption_check_size) + break; + if ((addr + size) > corruption_check_size) size = corruption_check_size - addr; - if (size == 0) - break; - e820_update_range(addr, size, E820_RAM, E820_RESERVED); scan_areas[num_scan_areas].addr = addr; scan_areas[num_scan_areas].size = size; -- cgit v1.2.3