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 5.15 19/42] x86/speculation: Fix RSB filling with CONFIG_RETPOLINE=n
Date: Tue, 19 Jul 2022 21:13:27 -0400 [thread overview]
Message-ID: <20220720011350.1024134-19-sashal@kernel.org> (raw)
In-Reply-To: <20220720011350.1024134-1-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 00413e37feee..5bd3baf36d87 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -701,7 +701,6 @@ SYM_CODE_START(__switch_to_asm)
movl %ebx, PER_CPU_VAR(__stack_chk_guard)
#endif
-#ifdef CONFIG_RETPOLINE
/*
* When switching from a shallower to a deeper call stack
* the RSB may either underflow or use entries populated
@@ -710,7 +709,6 @@ 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 3acf0af49305..9ab88798c504 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -243,7 +243,6 @@ 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
@@ -252,7 +251,6 @@ 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 e3f2dbea0a09..6189609bede3 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -102,11 +102,9 @@
* 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 1:20 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-20 1:13 [PATCH AUTOSEL 5.15 01/42] Revert "evm: Fix memleak in init_desc" Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 02/42] ARM: rockchip: Add missing of_node_put() in rockchip_suspend_init() Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 03/42] x86/kvm/vmx: Make noinstr clean Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 04/42] x86/cpufeatures: Move RETPOLINE flags to word 11 Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 05/42] x86/retpoline: Swizzle retpoline thunk Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 06/42] x86/vsyscall_emu/64: Don't use RET in vsyscall emulation Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 07/42] x86/sev: Avoid using __x86_return_thunk Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 08/42] objtool: Treat .text.__x86.* as noinstr Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 09/42] x86/bugs: Report AMD retbleed vulnerability Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 10/42] x86/bugs: Add AMD retbleed= boot parameter Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 11/42] x86/bugs: Enable STIBP for JMP2RET Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 12/42] x86/bugs: Keep a per-CPU IA32_SPEC_CTRL value Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 13/42] x86/bugs: Optimize SPEC_CTRL MSR writes Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 14/42] x86/bugs: Split spectre_v2_select_mitigation() and spectre_v2_user_select_mitigation() Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 15/42] x86/bugs: Report Intel retbleed vulnerability Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 16/42] x86/xen: Rename SYS* entry points Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 17/42] x86/bugs: Do IBPB fallback check only once Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 18/42] x86/cpu/amd: Add Spectral Chicken Sasha Levin
2022-07-20 1:13 ` Sasha Levin [this message]
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 20/42] KVM: VMX: Flatten __vmx_vcpu_run() Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 21/42] KVM: VMX: Convert launched argument to flags Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 22/42] KVM: VMX: Prevent guest RSB poisoning attacks with eIBRS Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 23/42] wifi: mac80211: check skb_shared in ieee80211_8023_xmit() Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 24/42] wifi: mac80211: do not wake queues on a vif that is being stopped Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 25/42] wifi: cfg80211: Allow P2P client interface to indicate port authorization Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 26/42] drm: panel-orientation-quirks: Add quirk for the Lenovo Yoga Tablet 2 830 Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 27/42] nilfs2: fix incorrect masking of permission flags for symlinks Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 28/42] ASoC: ti: omap-mcbsp: duplicate sysfs error Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 29/42] ASoC: tlv320adcx140: Fix tx_mask check Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 30/42] ASoC: wm5102: Fix event generation for output compensation Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 31/42] ASoC: wm8998: Fix event generation for input mux Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 32/42] ASoC: cs47l92: Fix event generation for OUT1 demux Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 33/42] ASoC: arizona: Update arizona_aif_cfg_changed to use RX_BCLK_RATE Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 34/42] scsi: target: Fix WRITE_SAME No Data Buffer crash Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 35/42] x86/kexec: Disable RET on kexec Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 36/42] platform/x86: asus-wmi: Add key mappings Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 37/42] platform/x86: intel_atomisp2_led: Also turn off the always-on camera LED on the Asus T100TAF Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 38/42] scsi: ufs: core: Fix missing clk change notification on host reset Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 39/42] scsi: pm80xx: Fix 'Unknown' max/min linkrate Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 40/42] scsi: pm80xx: Set stopped phy's linkrate to Disabled Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 41/42] KVM: nVMX: Always enable TSC scaling for L2 when it was enabled for L1 Sasha Levin
2022-07-20 1:13 ` [PATCH AUTOSEL 5.15 42/42] ubsan: disable UBSAN_DIV_ZERO for clang Sasha Levin
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