linux/arch/x86
Nadav Amit e836673c9b x86/alternatives: Add text_poke_kgdb() to not assert the lock when debugging
text_mutex is currently expected to be held before text_poke() is
called, but kgdb does not take the mutex, and instead *supposedly*
ensures the lock is not taken and will not be acquired by any other core
while text_poke() is running.

The reason for the "supposedly" comment is that it is not entirely clear
that this would be the case if gdb_do_roundup is zero.

Create two wrapper functions, text_poke() and text_poke_kgdb(), which do
or do not run the lockdep assertion respectively.

While we are at it, change the return code of text_poke() to something
meaningful. One day, callers might actually respect it and the existing
BUG_ON() when patching fails could be removed. For kgdb, the return
value can actually be used.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Cc: <akpm@linux-foundation.org>
Cc: <ard.biesheuvel@linaro.org>
Cc: <deneen.t.dock@intel.com>
Cc: <kernel-hardening@lists.openwall.com>
Cc: <kristen@linux.intel.com>
Cc: <linux_dti@icloud.com>
Cc: <will.deacon@arm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 9222f60650 ("x86/alternatives: Lockdep-enforce text_mutex in text_poke*()")
Link: https://lkml.kernel.org/r/20190426001143.4983-2-namit@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-30 12:37:47 +02:00
..
boot x86/boot: Disable RSDP parsing temporarily 2019-04-22 11:36:43 +02:00
configs Merge branch 'akpm' (patches from Andrew) 2019-03-07 19:25:37 -08:00
crypto crypto: x86/poly1305 - fix overflow during partial reduction 2019-04-08 14:43:06 +08:00
entry pidfd patches for v5.1-rc1 2019-03-16 13:47:14 -07:00
events perf/x86/intel: Update KBL Package C-state events to also include PC8/PC9/PC10 counters 2019-04-25 08:59:31 +02:00
hyperv x86/hyperv: Prevent potential NULL pointer dereference 2019-03-21 12:24:39 +01:00
ia32 a.out: remove core dumping support 2019-03-05 10:00:35 -08:00
include x86/alternatives: Add text_poke_kgdb() to not assert the lock when debugging 2019-04-30 12:37:47 +02:00
kernel x86/alternatives: Add text_poke_kgdb() to not assert the lock when debugging 2019-04-30 12:37:47 +02:00
kvm KVM: x86: avoid misreporting level-triggered irqs as edge-triggered in tracing 2019-04-16 15:38:08 +02:00
lib x86/lib: Fix indentation issue, remove extra tab 2019-03-21 12:24:38 +01:00
math-emu
mm Linux 5.1-rc7 2019-04-30 07:51:54 +02:00
net
oprofile
pci x86/PCI: Fixup RTIT_BAR of Intel Denverton Trace Hub 2019-02-07 08:43:58 -06:00
platform x86/realmode: Make set_real_mode_mem() static inline 2019-03-29 10:16:27 +01:00
power
purgatory
ras
realmode x86/realmode: Make set_real_mode_mem() static inline 2019-03-29 10:16:27 +01:00
tools
um Merge branch 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-03-05 14:08:26 -08:00
video
xen Merge branch 'akpm' (patches from Andrew) 2019-03-12 10:39:53 -07:00
.gitignore
Kbuild
Kconfig Merge branch 'linus' into x86/mm, to pick up dependent fix 2019-04-26 12:01:33 +02:00
Kconfig.cpu
Kconfig.debug
Makefile x86/retpolines: Disable switch jump tables when retpolines are enabled 2019-03-28 13:39:48 +01:00
Makefile.um
Makefile_32.cpu