From: Andy Lutomirski <luto@kernel.org>
To: X86 ML <x86@kernel.org>
Cc: Borislav Petkov <bpetkov@suse.de>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Brian Gerst <brgerst@gmail.com>,
Dave Hansen <dave.hansen@intel.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Andy Lutomirski <luto@kernel.org>
Subject: [PATCH v2 01/20] x86/asm/64: Remove the restore_c_regs_and_iret label
Date: Thu, 2 Nov 2017 00:58:58 -0700 [thread overview]
Message-ID: <be3006a7ad3326e3458cf1cc55d416252cbe1986.1509609304.git.luto@kernel.org> (raw)
In-Reply-To: <cover.1509609304.git.luto@kernel.org>
In-Reply-To: <cover.1509609304.git.luto@kernel.org>
The only user was the 64-bit opportunistic SYSRET failure path, and
that path didn't really need it. This change makes the
opportunistic SYSRET code a bit more straightforward and gets rid of
the label.
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
arch/x86/entry/entry_64.S | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 49167258d587..afe1f403fa0e 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -245,7 +245,6 @@ entry_SYSCALL64_slow_path:
call do_syscall_64 /* returns with IRQs disabled */
return_from_SYSCALL_64:
- RESTORE_EXTRA_REGS
TRACE_IRQS_IRETQ /* we're about to change IF */
/*
@@ -314,6 +313,7 @@ return_from_SYSCALL_64:
*/
syscall_return_via_sysret:
/* rcx and r11 are already restored (see code above) */
+ RESTORE_EXTRA_REGS
RESTORE_C_REGS_EXCEPT_RCX_R11
movq RSP(%rsp), %rsp
UNWIND_HINT_EMPTY
@@ -321,7 +321,7 @@ syscall_return_via_sysret:
opportunistic_sysret_failed:
SWAPGS
- jmp restore_c_regs_and_iret
+ jmp restore_regs_and_iret
END(entry_SYSCALL_64)
ENTRY(stub_ptregs_64)
@@ -638,7 +638,6 @@ retint_kernel:
*/
GLOBAL(restore_regs_and_iret)
RESTORE_EXTRA_REGS
-restore_c_regs_and_iret:
RESTORE_C_REGS
REMOVE_PT_GPREGS_FROM_STACK 8
INTERRUPT_RETURN
--
2.13.6
next prev parent reply other threads:[~2017-11-02 7:59 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-02 7:58 [PATCH v2 00/20] Pile o' entry/exit/sp0 changes Andy Lutomirski
2017-11-02 7:58 ` Andy Lutomirski [this message]
2017-11-02 10:49 ` [tip:x86/asm] x86/entry/64: Remove the restore_c_regs_and_iret label tip-bot for Andy Lutomirski
2017-11-02 7:58 ` [PATCH v2 02/20] x86/asm/64: Split the iret-to-user and iret-to-kernel paths Andy Lutomirski
2017-11-02 10:49 ` [tip:x86/asm] x86/entry/64: Split the IRET-to-user and IRET-to-kernel paths tip-bot for Andy Lutomirski
2017-11-02 10:50 ` [PATCH v2 02/20] x86/asm/64: Split the iret-to-user and iret-to-kernel paths Borislav Petkov
2017-11-02 12:09 ` [PATCH] x86/entry/64: Shorten TEST instructions Borislav Petkov
2017-11-02 12:48 ` [tip:x86/asm] " tip-bot for Borislav Petkov
2017-11-02 7:59 ` [PATCH v2 03/20] x86/asm/64: Move SWAPGS into the common iret-to-usermode path Andy Lutomirski
2017-11-02 10:49 ` [tip:x86/asm] x86/entry/64: Move SWAPGS into the common IRET-to-usermode path tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 04/20] x86/asm/64: Simplify reg restore code in the standard IRET paths Andy Lutomirski
2017-11-02 10:50 ` [tip:x86/asm] x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 05/20] x86/asm/64: Shrink paranoid_exit_restore and make labels local Andy Lutomirski
2017-11-02 10:50 ` [tip:x86/asm] x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 06/20] x86/asm/64: Use pop instead of movq in syscall_return_via_sysret Andy Lutomirski
2017-11-02 10:51 ` [tip:x86/asm] x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 07/20] x86/asm/64: Merge the fast and slow SYSRET paths Andy Lutomirski
2017-11-02 10:51 ` [tip:x86/asm] x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 08/20] x86/entry/64: Use POP instead of MOV to restore regs on NMI return Andy Lutomirski
2017-11-02 10:51 ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 09/20] x86/entry/64: Remove the RESTORE_..._REGS infrastructure Andy Lutomirski
2017-11-02 10:52 ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 10/20] xen: add xen nmi trap entry Andy Lutomirski
2017-11-02 10:52 ` [tip:x86/asm] xen, x86/entry/64: Add xen NMI " tip-bot for Juergen Gross
2017-11-02 7:59 ` [PATCH v2 11/20] x86/asm/64: De-Xen-ify our NMI code Andy Lutomirski
2017-11-02 10:53 ` [tip:x86/asm] x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 12/20] x86/asm/32: Pull MSR_IA32_SYSENTER_CS update code out of native_load_sp0() Andy Lutomirski
2017-11-02 10:53 ` [tip:x86/asm] x86/entry/32: Pull the " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 13/20] x86/asm/64: Pass sp0 directly to load_sp0() Andy Lutomirski
2017-11-02 9:48 ` Ingo Molnar
2017-11-02 9:53 ` Ingo Molnar
2017-11-02 10:32 ` Andy Lutomirski
2017-11-02 10:53 ` [tip:x86/asm] x86/entry/64: Pass SP0 " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 14/20] x86/asm: Add task_top_of_stack() to find the top of a task's stack Andy Lutomirski
2017-11-02 10:54 ` [tip:x86/asm] x86/entry: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 15/20] x86/xen/64: Clean up SP code in cpu_initialize_context() Andy Lutomirski
2017-11-02 9:56 ` Juergen Gross
2017-11-02 10:54 ` [tip:x86/asm] x86/xen/64, x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 16/20] x86/boot/64: Stop initializing TSS.sp0 at boot Andy Lutomirski
2017-11-02 10:55 ` [tip:x86/asm] x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 17/20] x86/asm/64: Remove all remaining direct thread_struct::sp0 reads Andy Lutomirski
2017-11-02 10:55 ` [tip:x86/asm] x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 18/20] x86/boot/32: Fix cpu_current_top_of_stack initialization at boot Andy Lutomirski
2017-11-02 10:56 ` [tip:x86/asm] x86/entry/32: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 19/20] x86/asm/64: Remove thread_struct::sp0 Andy Lutomirski
2017-11-02 10:56 ` [tip:x86/asm] x86/entry/64: " tip-bot for Andy Lutomirski
2017-11-02 7:59 ` [PATCH v2 20/20] x86/traps: Use a new on_thread_stack() helper to clean up an assertion Andy Lutomirski
2017-11-02 10:56 ` [tip:x86/asm] " tip-bot for Andy Lutomirski
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=be3006a7ad3326e3458cf1cc55d416252cbe1986.1509609304.git.luto@kernel.org \
--to=luto@kernel.org \
--cc=bpetkov@suse.de \
--cc=brgerst@gmail.com \
--cc=dave.hansen@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).