From 85a0ee342e0c06c19d78fdf48307211c6cf18fcb Mon Sep 17 00:00:00 2001 From: Simon Horman Date: Sat, 18 Oct 2008 20:28:29 -0700 Subject: kdump: add is_vmcore_usable() and vmcore_unusable() The usage of elfcorehdr_addr has changed recently such that being set to ELFCORE_ADDR_MAX is used by is_kdump_kernel() to indicate if the code is executing in a kernel executed as a crash kernel. However, arch/ia64/kernel/setup.c:reserve_elfcorehdr will rest elfcorehdr_addr to ELFCORE_ADDR_MAX on error, which means any subsequent calls to is_kdump_kernel() will return 0, even though they should return 1. Ok, at this point in time there are no subsequent calls, but I think its fair to say that there is ample scope for error or at the very least confusion. This patch add an extra state, ELFCORE_ADDR_ERR, which indicates that elfcorehdr_addr was passed on the command line, and thus execution is taking place in a crashdump kernel, but vmcore can't be used for some reason. This is tested for using is_vmcore_usable() and set using vmcore_unusable(). A subsequent patch makes use of this new code. To summarise, the states that elfcorehdr_addr can now be in are as follows: ELFCORE_ADDR_MAX: not a crashdump kernel ELFCORE_ADDR_ERR: crashdump kernel but vmcore is unusable any other value: crash dump kernel and vmcore is usable Signed-off-by: Simon Horman Cc: Vivek Goyal Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ia64/kernel/setup.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/ia64') diff --git a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c index a0286be6c235..60286522d54a 100644 --- a/arch/ia64/kernel/setup.c +++ b/arch/ia64/kernel/setup.c @@ -509,11 +509,11 @@ int __init reserve_elfcorehdr(unsigned long *start, unsigned long *end) * to work properly. */ - if (elfcorehdr_addr >= ELFCORE_ADDR_MAX) + if (!is_vmcore_usable()) return -EINVAL; if ((length = vmcore_find_descriptor_size(elfcorehdr_addr)) == 0) { - elfcorehdr_addr = ELFCORE_ADDR_MAX; + vmcore_unusable(); return -EINVAL; } -- cgit v1.2.3