From 815d5704a337a662bf960757edbff7a0680d40fd Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Fri, 8 Aug 2014 14:25:52 -0700 Subject: kexec: make kexec_segment user buffer pointer a union So far kexec_segment->buf was always a user space pointer as user space passed the array of kexec_segment structures and kernel copied it. But with new system call, list of kexec segments will be prepared by kernel and kexec_segment->buf will point to a kernel memory. So while I was adding code where I made assumption that ->buf is pointing to kernel memory, sparse started giving warning. Make ->buf a union. And where a user space pointer is expected, access it using ->buf and where a kernel space pointer is expected, access it using ->kbuf. That takes care of sparse warnings. Signed-off-by: Vivek Goyal Cc: Borislav Petkov Cc: Michael Kerrisk Cc: Yinghai Lu Cc: Eric Biederman Cc: H. Peter Anvin Cc: Matthew Garrett Cc: Greg Kroah-Hartman Cc: Dave Young Cc: WANG Chao Cc: Baoquan He Cc: Andy Lutomirski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/kexec.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'include/linux/kexec.h') diff --git a/include/linux/kexec.h b/include/linux/kexec.h index d9bb0a57d208..66d56ac0f64c 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -69,7 +69,18 @@ typedef unsigned long kimage_entry_t; #define IND_SOURCE 0x8 struct kexec_segment { - void __user *buf; + /* + * This pointer can point to user memory if kexec_load() system + * call is used or will point to kernel memory if + * kexec_file_load() system call is used. + * + * Use ->buf when expecting to deal with user memory and use ->kbuf + * when expecting to deal with kernel memory. + */ + union { + void __user *buf; + void *kbuf; + }; size_t bufsz; unsigned long mem; size_t memsz; -- cgit v1.2.3-59-g8ed1b