diff options
author | Vivek Goyal <vgoyal@redhat.com> | 2014-08-29 15:18:46 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-29 16:28:16 -0700 |
commit | 74ca317c26a3f8543203b61d262c0ab2e30c384e (patch) | |
tree | e88c78846c33bd3f86034b2ba16616ea38bb2802 /kernel/kexec.c | |
parent | b38af4721f59d0b564468f623b3e52a638195015 (diff) | |
download | linux-74ca317c26a3f8543203b61d262c0ab2e30c384e.tar.bz2 |
kexec: create a new config option CONFIG_KEXEC_FILE for new syscall
Currently new system call kexec_file_load() and all the associated code
compiles if CONFIG_KEXEC=y. But new syscall also compiles purgatory
code which currently uses gcc option -mcmodel=large. This option seems
to be available only gcc 4.4 onwards.
Hiding new functionality behind a new config option will not break
existing users of old gcc. Those who wish to enable new functionality
will require new gcc. Having said that, I am trying to figure out how
can I move away from using -mcmodel=large but that can take a while.
I think there are other advantages of introducing this new config
option. As this option will be enabled only on x86_64, other arches
don't have to compile generic kexec code which will never be used. This
new code selects CRYPTO=y and CRYPTO_SHA256=y. And all other arches had
to do this for CONFIG_KEXEC. Now with introduction of new config
option, we can remove crypto dependency from other arches.
Now CONFIG_KEXEC_FILE is available only on x86_64. So whereever I had
CONFIG_X86_64 defined, I got rid of that.
For CONFIG_KEXEC_FILE, instead of doing select CRYPTO=y, I changed it to
"depends on CRYPTO=y". This should be safer as "select" is not
recursive.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Tested-by: Shaun Ruffell <sruffell@digium.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/kexec.c')
-rw-r--r-- | kernel/kexec.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/kernel/kexec.c b/kernel/kexec.c index 0b49a0a58102..2bee072268d9 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -64,7 +64,9 @@ bool kexec_in_progress = false; char __weak kexec_purgatory[0]; size_t __weak kexec_purgatory_size = 0; +#ifdef CONFIG_KEXEC_FILE static int kexec_calculate_store_digests(struct kimage *image); +#endif /* Location of the reserved area for the crash kernel */ struct resource crashk_res = { @@ -341,6 +343,7 @@ out_free_image: return ret; } +#ifdef CONFIG_KEXEC_FILE static int copy_file_from_fd(int fd, void **buf, unsigned long *buf_len) { struct fd f = fdget(fd); @@ -612,6 +615,9 @@ out_free_image: kfree(image); return ret; } +#else /* CONFIG_KEXEC_FILE */ +static inline void kimage_file_post_load_cleanup(struct kimage *image) { } +#endif /* CONFIG_KEXEC_FILE */ static int kimage_is_destination_range(struct kimage *image, unsigned long start, @@ -1375,6 +1381,7 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry, } #endif +#ifdef CONFIG_KEXEC_FILE SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, unsigned long, cmdline_len, const char __user *, cmdline_ptr, unsigned long, flags) @@ -1451,6 +1458,8 @@ out: return ret; } +#endif /* CONFIG_KEXEC_FILE */ + void crash_kexec(struct pt_regs *regs) { /* Take the kexec_mutex here to prevent sys_kexec_load @@ -2006,6 +2015,7 @@ static int __init crash_save_vmcoreinfo_init(void) subsys_initcall(crash_save_vmcoreinfo_init); +#ifdef CONFIG_KEXEC_FILE static int __kexec_add_segment(struct kimage *image, char *buf, unsigned long bufsz, unsigned long mem, unsigned long memsz) @@ -2682,6 +2692,7 @@ int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, return 0; } +#endif /* CONFIG_KEXEC_FILE */ /* * Move into place and start executing a preloaded standalone |