This is a note to let you know that I've just added the patch titled
x86/entry: Remove skip_r11rcx
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-entry-remove-skip_r11rcx.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Mon Oct 31 07:55:50 AM CET 2022
From: Suraj Jitindar Singh <surajjs@xxxxxxxxxx>
Date: Thu, 27 Oct 2022 13:54:41 -0700
Subject: x86/entry: Remove skip_r11rcx
To: <stable@xxxxxxxxxxxxxxx>
Cc: <surajjs@xxxxxxxxxx>, <sjitindarsingh@xxxxxxxxx>, <cascardo@xxxxxxxxxxxxx>, <kvm@xxxxxxxxxxxxxxx>, <pbonzini@xxxxxxxxxx>, <jpoimboe@xxxxxxxxxx>, <peterz@xxxxxxxxxxxxx>, <x86@xxxxxxxxxx>
Message-ID: <20221027205442.17210-3-surajjs@xxxxxxxxxx>
From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
commit 1b331eeea7b8676fc5dbdf80d0a07e41be226177 upstream.
Yes, r11 and rcx have been restored previously, but since they're being
popped anyway (into rsi) might as well pop them into their own regs --
setting them to the value they already are.
Less magical code.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lore.kernel.org/r/20220506121631.365070674@xxxxxxxxxxxxx
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/entry/calling.h | 10 +---------
arch/x86/entry/entry_64.S | 3 +--
2 files changed, 2 insertions(+), 11 deletions(-)
--- a/arch/x86/entry/calling.h
+++ b/arch/x86/entry/calling.h
@@ -146,27 +146,19 @@ For 32-bit we have the following convent
.endm
-.macro POP_REGS pop_rdi=1 skip_r11rcx=0
+.macro POP_REGS pop_rdi=1
popq %r15
popq %r14
popq %r13
popq %r12
popq %rbp
popq %rbx
- .if \skip_r11rcx
- popq %rsi
- .else
popq %r11
- .endif
popq %r10
popq %r9
popq %r8
popq %rax
- .if \skip_r11rcx
- popq %rsi
- .else
popq %rcx
- .endif
popq %rdx
popq %rsi
.if \pop_rdi
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -301,8 +301,7 @@ GLOBAL(entry_SYSCALL_64_after_hwframe)
* perf profiles. Nothing jumps here.
*/
syscall_return_via_sysret:
- /* rcx and r11 are already restored (see code above) */
- POP_REGS pop_rdi=0 skip_r11rcx=1
+ POP_REGS pop_rdi=0
/*
* Now all regs are restored except RSP and RDI.
Patches currently in stable-queue which might be from surajjs@xxxxxxxxxx are
queue-4.14/x86-speculation-disable-rrsba-behavior.patch
queue-4.14/x86-bugs-report-intel-retbleed-vulnerability.patch
queue-4.14/x86-entry-add-kernel-ibrs-implementation.patch
queue-4.14/x86-bugs-warn-when-ibrs-mitigation-is-selected-on-enhanced-ibrs-parts.patch
queue-4.14/x86-cpu-add-a-steppings-field-to-struct-x86_cpu_id.patch
queue-4.14/x86-speculation-fix-spec_ctrl-write-on-smt-state-change.patch
queue-4.14/entel_idle-disable-ibrs-during-long-idle.patch
queue-4.14/x86-speculation-use-cached-host-spec_ctrl-value-for-guest-entry-exit.patch
queue-4.14/x86-speculation-change-fill_return_buffer-to-work-with-objtool.patch
queue-4.14/x86-speculation-add-lfence-to-rsb-fill-sequence.patch
queue-4.14/x86-bugs-report-amd-retbleed-vulnerability.patch
queue-4.14/x86-speculation-add-spectre_v2-ibrs-option-to-support-kernel-ibrs.patch
queue-4.14/x86-bugs-keep-a-per-cpu-ia32_spec_ctrl-value.patch
queue-4.14/x86-speculation-fill-rsb-on-vmexit-for-ibrs.patch
queue-4.14/x86-speculation-fix-rsb-filling-with-config_retpoline-n.patch
queue-4.14/x86-speculation-add-rsb-vm-exit-protections.patch
queue-4.14/x86-bugs-optimize-spec_ctrl-msr-writes.patch
queue-4.14/kvm-vmx-fix-ibrs-handling-after-vmexit.patch
queue-4.14/kvm-vmx-prevent-guest-rsb-poisoning-attacks-with-eibrs.patch
queue-4.14/x86-speculation-fix-firmware-entry-spec_ctrl-handling.patch
queue-4.14/x86-bugs-add-amd-retbleed-boot-parameter.patch
queue-4.14/x86-cpu-add-consistent-cpu-match-macros.patch
queue-4.14/x86-speculation-remove-x86_spec_ctrl_mask.patch
queue-4.14/x86-speculation-use-declare_per_cpu-for-x86_spec_ctrl_current.patch
queue-4.14/x86-cpufeature-fix-various-quality-problems-in-the-asm-cpu_device_hd.h-header.patch
queue-4.14/x86-entry-remove-skip_r11rcx.patch
queue-4.14/revert-x86-cpu-add-a-steppings-field-to-struct-x86_cpu_id.patch
queue-4.14/x86-common-stamp-out-the-stepping-madness.patch
queue-4.14/x86-cpu-amd-enumerate-btc_no.patch
queue-4.14/x86-bugs-add-cannon-lake-to-retbleed-affected-cpu-list.patch
queue-4.14/x86-devicetable-move-x86-specific-macro-out-of-generic-code.patch
queue-4.14/x86-bugs-split-spectre_v2_select_mitigation-and-spectre_v2_user_select_mitigation.patch
queue-4.14/x86-cpufeatures-move-retpoline-flags-to-word-11.patch
queue-4.14/x86-cpufeature-add-facility-to-check-for-min-microcode-revisions.patch
