]> git.proxmox.com Git - mirror_ubuntu-disco-kernel.git/commit
x86/boot: Rework reserve_real_mode() to allow multiple tries
authorAndy Lutomirski <luto@kernel.org>
Wed, 10 Aug 2016 09:29:16 +0000 (02:29 -0700)
committerIngo Molnar <mingo@kernel.org>
Thu, 11 Aug 2016 09:15:01 +0000 (11:15 +0200)
commit5ff3e2c3c3eebe13967d81ad1f23b9468fefea81
treeebd7923f9c8eb5d48710b8228577ea20f857c65c
parentd0de0f685db7faf2ae4597a39a59996dd84e18c7
x86/boot: Rework reserve_real_mode() to allow multiple tries

If reserve_real_mode() fails, panicing immediately means we're
doomed.  Make it safe to try more than once to allocate the
trampoline:

 - Degrade a failure from panic() to pr_info().  (If we make it to
   setup_real_mode() without reserving the trampoline, we'll panic
   them.)

 - Factor out helpers so that platform code can supply a specific
   address to try.

 - Warn if reserve_real_mode() is called after we're done with the
   memblock allocator.  If that were to happen, we would behave
   unpredictably.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/876e383038f3e9971aa72fd20a4f5da05f9d193d.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/include/asm/realmode.h
arch/x86/realmode/init.c