From 921d58c0e6992f74d3a48180604a298f115d2dee Mon Sep 17 00:00:00 2001 From: Magnus Damm Date: Wed, 7 Jan 2009 18:09:06 -0800 Subject: vmcore: remove saved_max_pfn check Remove the saved_max_pfn check from the /proc/vmcore function read_from_oldmem(). No need to verify, we should be able to just trust that "elfcorehdr=" is correctly passed to the crash kernel on the kernel command line like we do with other parameters. The read_from_oldmem() function in fs/proc/vmcore.c is quite similar to read_from_oldmem() in drivers/char/mem.c, but only in the latter it makes sense to use saved_max_pfn. For oldmem it is used to determine when to stop reading. For vmcore we already have the elf header info pointing out the physical memory regions, no need to pass the end-of- old-memory twice. Removing the saved_max_pfn check from vmcore makes it possible for architectures to skip oldmem but still support crash dump through vmcore - without the need for the old saved_max_pfn cruft. Architectures that want to play safe can do the saved_max_pfn check in copy_oldmem_page(). Not sure why anyone would want to do that, but that's even safer than today - the saved_max_pfn check in vmcore removed by this patch only checks the first page. Signed-off-by: Magnus Damm Acked-by: Vivek Goyal Acked-by: Simon Horman Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/vmcore.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'fs/proc') diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index 03ec59504906..5edcc3f92ba7 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -47,8 +47,6 @@ static ssize_t read_from_oldmem(char *buf, size_t count, offset = (unsigned long)(*ppos % PAGE_SIZE); pfn = (unsigned long)(*ppos / PAGE_SIZE); - if (pfn > saved_max_pfn) - return -EINVAL; do { if (count > (PAGE_SIZE - offset)) -- cgit v1.2.2