From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Josh Poimboeuf <jpoimboe@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Borislav Petkov <bp@suse.de>, Sasha Levin <sashal@kernel.org>,
luto@kernel.org, tglx@linutronix.de, mingo@redhat.com,
bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org,
pawan.kumar.gupta@linux.intel.com
Subject: [PATCH AUTOSEL 5.10 09/25] x86/speculation: Fix RSB filling with CONFIG_RETPOLINE=n
Date: Tue, 19 Jul 2022 21:16:00 -0400 [thread overview]
Message-ID: <20220720011616.1024753-9-sashal@kernel.org> (raw)
In-Reply-To: <20220720011616.1024753-1-sashal@kernel.org>
From: Josh Poimboeuf <jpoimboe@kernel.org>
[ Upstream commit b2620facef4889fefcbf2e87284f34dcd4189bce ]
If a kernel is built with CONFIG_RETPOLINE=n, but the user still wants
to mitigate Spectre v2 using IBRS or eIBRS, the RSB filling will be
silently disabled.
There's nothing retpoline-specific about RSB buffer filling. Remove the
CONFIG_RETPOLINE guards around it.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/entry/entry_32.S | 2 --
arch/x86/entry/entry_64.S | 2 --
arch/x86/include/asm/nospec-branch.h | 2 --
3 files changed, 6 deletions(-)
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index df8c017e6161..6c8f0a664fc9 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -782,7 +782,6 @@ SYM_CODE_START(__switch_to_asm)
movl %ebx, PER_CPU_VAR(stack_canary)+stack_canary_offset
#endif
-#ifdef CONFIG_RETPOLINE
/*
* When switching from a shallower to a deeper call stack
* the RSB may either underflow or use entries populated
@@ -791,7 +790,6 @@ SYM_CODE_START(__switch_to_asm)
* speculative execution to prevent attack.
*/
FILL_RETURN_BUFFER %ebx, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_CTXSW
-#endif
/* Restore flags or the incoming task to restore AC state. */
popfl
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 2f2d52729e17..64008a685fa1 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -244,7 +244,6 @@ SYM_FUNC_START(__switch_to_asm)
movq %rbx, PER_CPU_VAR(fixed_percpu_data) + stack_canary_offset
#endif
-#ifdef CONFIG_RETPOLINE
/*
* When switching from a shallower to a deeper call stack
* the RSB may either underflow or use entries populated
@@ -253,7 +252,6 @@ SYM_FUNC_START(__switch_to_asm)
* speculative execution to prevent attack.
*/
FILL_RETURN_BUFFER %r12, RSB_CLEAR_LOOPS, X86_FEATURE_RSB_CTXSW
-#endif
/* restore callee-saved registers */
popq %r15
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 18eeede6ad77..40f6b640cc51 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -103,11 +103,9 @@
* monstrosity above, manually.
*/
.macro FILL_RETURN_BUFFER reg:req nr:req ftr:req
-#ifdef CONFIG_RETPOLINE
ALTERNATIVE "jmp .Lskip_rsb_\@", "", \ftr
__FILL_RETURN_BUFFER(\reg,\nr,%_ASM_SP)
.Lskip_rsb_\@:
-#endif
.endm
#else /* __ASSEMBLY__ */
--
2.35.1
next prev parent reply other threads:[~2022-07-20 1:24 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-20 1:15 [PATCH AUTOSEL 5.10 01/25] Revert "evm: Fix memleak in init_desc" Sasha Levin
2022-07-20 1:15 ` [PATCH AUTOSEL 5.10 02/25] ARM: rockchip: Add missing of_node_put() in rockchip_suspend_init() Sasha Levin
2022-07-20 1:15 ` [PATCH AUTOSEL 5.10 03/25] x86/kvm/vmx: Make noinstr clean Sasha Levin
2022-07-20 1:15 ` [PATCH AUTOSEL 5.10 04/25] objtool: Treat .text.__x86.* as noinstr Sasha Levin
2022-07-20 1:15 ` [PATCH AUTOSEL 5.10 05/25] x86/bugs: Report AMD retbleed vulnerability Sasha Levin
2022-07-20 7:48 ` Greg KH
2022-07-20 16:37 ` Sasha Levin
2022-07-20 1:15 ` [PATCH AUTOSEL 5.10 06/25] x86/bugs: Keep a per-CPU IA32_SPEC_CTRL value Sasha Levin
2022-07-20 1:15 ` [PATCH AUTOSEL 5.10 07/25] x86/bugs: Optimize SPEC_CTRL MSR writes Sasha Levin
2022-07-20 1:15 ` [PATCH AUTOSEL 5.10 08/25] x86/cpu/amd: Add Spectral Chicken Sasha Levin
2022-07-20 1:16 ` Sasha Levin [this message]
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 10/25] wifi: mac80211: check skb_shared in ieee80211_8023_xmit() Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 11/25] wifi: mac80211: do not wake queues on a vif that is being stopped Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 12/25] wifi: cfg80211: Allow P2P client interface to indicate port authorization Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 13/25] drm: panel-orientation-quirks: Add quirk for the Lenovo Yoga Tablet 2 830 Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 14/25] nilfs2: fix incorrect masking of permission flags for symlinks Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 15/25] ASoC: ti: omap-mcbsp: duplicate sysfs error Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 16/25] ASoC: tlv320adcx140: Fix tx_mask check Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 17/25] ASoC: wm8998: Fix event generation for input mux Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 18/25] ASoC: cs47l92: Fix event generation for OUT1 demux Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 19/25] ASoC: arizona: Update arizona_aif_cfg_changed to use RX_BCLK_RATE Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 20/25] scsi: target: Fix WRITE_SAME No Data Buffer crash Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 21/25] platform/x86: asus-wmi: Add key mappings Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 22/25] platform/x86: intel_atomisp2_led: Also turn off the always-on camera LED on the Asus T100TAF Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 23/25] scsi: ufs: core: Fix missing clk change notification on host reset Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 24/25] scsi: pm80xx: Fix 'Unknown' max/min linkrate Sasha Levin
2022-07-20 1:16 ` [PATCH AUTOSEL 5.10 25/25] scsi: pm80xx: Set stopped phy's linkrate to Disabled Sasha Levin
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