linux/arch/x86
Josh Poimboeuf 071c44e427 sched/idle: Mark arch_cpu_idle_dead() __noreturn
Before commit 076cbf5d2163 ("x86/xen: don't let xen_pv_play_dead()
return"), in Xen, when a previously offlined CPU was brought back
online, it unexpectedly resumed execution where it left off in the
middle of the idle loop.

There were some hacks to make that work, but the behavior was surprising
as do_idle() doesn't expect an offlined CPU to return from the dead (in
arch_cpu_idle_dead()).

Now that Xen has been fixed, and the arch-specific implementations of
arch_cpu_idle_dead() also don't return, give it a __noreturn attribute.

This will cause the compiler to complain if an arch-specific
implementation might return.  It also improves code generation for both
caller and callee.

Also fixes the following warning:

  vmlinux.o: warning: objtool: do_idle+0x25f: unreachable instruction

Reported-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/60d527353da8c99d4cf13b6473131d46719ed16d.1676358308.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2023-03-08 08:44:28 -08:00
..
boot Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
coco - Fixup comment typo 2023-02-25 09:11:30 -08:00
configs
crypto crypto: x86/aria-avx - Do not use avx2 instructions 2023-02-14 13:39:33 +08:00
entry Changes in this cycle were: 2023-03-02 09:45:34 -08:00
events ARM: 2023-02-25 11:30:21 -08:00
hyperv x86/hyperv: Remove unregister syscore call from Hyper-V cleanup 2022-11-29 17:55:29 +00:00
ia32 x86/signal/32: Merge native and compat 32-bit signal code 2022-10-19 09:58:49 +02:00
include x86/cpu: Mark play_dead() __noreturn 2023-03-08 08:44:26 -08:00
kernel sched/idle: Mark arch_cpu_idle_dead() __noreturn 2023-03-08 08:44:28 -08:00
kvm ARM: 2023-02-25 11:30:21 -08:00
lib - Cache the AMD debug registers in per-CPU variables to avoid MSR writes 2023-02-21 14:51:40 -08:00
math-emu
mm - Daniel Verkamp has contributed a memfd series ("mm/memfd: add 2023-02-23 17:09:35 -08:00
net bpf, x86: Simplify the parsing logic of structure parameters 2023-01-10 15:53:22 -08:00
pci x86/pci/xen: Fixup fallout from the PCI/MSI overhaul 2023-01-16 20:40:44 +01:00
platform A healthy mix of EFI contributions this time: 2023-02-23 14:41:48 -08:00
power - Add the call depth tracking mitigation for Retbleed which has 2022-12-14 15:03:00 -08:00
purgatory x86/purgatory: disable KMSAN instrumentation 2022-10-28 13:37:23 -07:00
ras
realmode x86/boot: Skip realmode init code when running as Xen PV guest 2022-11-25 12:05:22 +01:00
tools kbuild: allow to combine multiple V= levels 2023-01-22 23:43:32 +09:00
um This pull request contains the following changes for UML: 2023-03-01 09:13:00 -08:00
video
virt/vmx/tdx
xen xen: branch for v6.3-rc1 2023-02-21 17:07:39 -08:00
.gitignore
Kbuild
Kconfig x86/Kconfig: Fix spellos & punctuation 2023-01-25 12:21:04 +01:00
Kconfig.assembler crypto: x86/aria-avx - fix build failure with old binutils 2023-01-20 18:29:31 +08:00
Kconfig.cpu
Kconfig.debug
Makefile x86/build: Make 64-bit defconfig the default 2023-02-15 14:20:17 +01:00
Makefile_32.cpu
Makefile.um This pull request contains the following changes for UML: 2023-03-01 09:13:00 -08:00