From c6fca85f2153de8b2451269de43abcc2aa0213ab Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 4 May 2024 12:10:18 +0200 Subject: Merging upstream version 6.1.82. Signed-off-by: Daniel Baumann --- arch/x86/kernel/alternative.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'arch/x86/kernel/alternative.c') diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 6b8c93989..69f85e274 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -536,6 +536,7 @@ void __init_or_module noinline apply_retpolines(s32 *start, s32 *end) } #ifdef CONFIG_RETHUNK + /* * Rewrite the compiler generated return thunk tail-calls. * @@ -551,14 +552,18 @@ static int patch_return(void *addr, struct insn *insn, u8 *bytes) { int i = 0; - if (cpu_feature_enabled(X86_FEATURE_RETHUNK)) - return -1; + if (cpu_feature_enabled(X86_FEATURE_RETHUNK)) { + if (x86_return_thunk == __x86_return_thunk) + return -1; - bytes[i++] = RET_INSN_OPCODE; + i = JMP32_INSN_SIZE; + __text_gen_insn(bytes, JMP32_INSN_OPCODE, addr, x86_return_thunk, i); + } else { + bytes[i++] = RET_INSN_OPCODE; + } for (; i < insn->length;) bytes[i++] = INT3_INSN_OPCODE; - return i; } -- cgit v1.2.3