efi: Add comment to avoid future expanding of sysfs systab
/sys/firmware/efi/systab shows several different values, it breaks sysfs
one file one value design. But since there are already userspace tools
depend on it eg. kexec-tools so add code comment to alert future expanding
of this file.
Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20171206095010.24170-4-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index c3eefa1..557a478 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -109,6 +109,8 @@ struct kobject *efi_kobj;
/*
* Let's not leave out systab information that snuck into
* the efivars driver
+ * Note, do not add more fields in systab sysfs file as it breaks sysfs
+ * one value per file rule!
*/
static ssize_t systab_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)