From 7f614cd1e052ebbddee7ea49c725dc75fee74a5a Mon Sep 17 00:00:00 2001 From: HATAYAMA Daisuke Date: Wed, 3 Jul 2013 15:02:15 -0700 Subject: [PATCH] vmcore: treat memory chunks referenced by PT_LOAD program header entries in page-size boundary in vmcore_list Treat memory chunks referenced by PT_LOAD program header entries in page-size boundary in vmcore_list. Formally, for each range [start, end], we set up the corresponding vmcore object in vmcore_list to [rounddown(start, PAGE_SIZE), roundup(end, PAGE_SIZE)]. This change affects layout of /proc/vmcore. The gaps generated by the rearrangement are newly made visible to applications as holes. Concretely, they are two ranges [rounddown(start, PAGE_SIZE), start] and [end, roundup(end, PAGE_SIZE)]. Suppose variable m points at a vmcore object in vmcore_list, and variable phdr points at the program header of PT_LOAD type the variable m corresponds to. Then, pictorially: m->offset +---------------+ | hole | phdr->p_offset = +---------------+ m->offset + (paddr - start) | |\ | kernel memory | phdr->p_memsz | |/ +---------------+ | hole | m->offset + m->size +---------------+ where m->offset and m->offset + m->size are always page-size aligned. Signed-off-by: HATAYAMA Daisuke Acked-by: Vivek Goyal Cc: KOSAKI Motohiro Cc: Atsushi Kumagai Cc: Lisa Mitchell Cc: Zhang Yanfei Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-format-patch failed