Make sure the default return thunk is not used after all return instructions have been patched by the alternatives because the default return thunk is insufficient when it comes to mitigating Retbleed or SRSO. Fix based on an earlier version by David Kaplan <david.kaplan@amd.com>. [ bp: Fix the compilation error of warn_thunk_thunk being an invisible symbol, hoist thunk macro into calling.h ] Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Co-developed-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231010171020.462211-4-david.kaplan@amd.com Link: https://lore.kernel.org/r/20240104132446.GEZZaxnrIgIyat0pqf@fat_crate.local
18 lines
506 B
ArmAsm
18 lines
506 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Trampoline to trace irqs off. (otherwise CALLER_ADDR1 might crash)
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* Copyright 2008 by Steven Rostedt, Red Hat, Inc
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* (inspired by Andi Kleen's thunk_64.S)
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*/
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#include <linux/export.h>
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#include <linux/linkage.h>
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#include <asm/asm.h>
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#include "calling.h"
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THUNK preempt_schedule_thunk, preempt_schedule
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THUNK preempt_schedule_notrace_thunk, preempt_schedule_notrace
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EXPORT_SYMBOL(preempt_schedule_thunk)
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EXPORT_SYMBOL(preempt_schedule_notrace_thunk)
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