From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6FCF3350843; Tue, 26 Aug 2025 14:42:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756219354; cv=none; b=WMEHRHEB3Lo1V0rXC1uDMFtf6ajUH3P1MI64VWa4wYVY78baFuT/K5knA6FLt9B3HUfj2yVYbvcdnHxnO1wayndVQKy/J39BfG+Vvt3S4Y/2tkusTvbHW0sSiMWFq0DQ4oJrUpbCJDz0z/XsPzhgW5E6ePDix+gxVn/3zCgKSew= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756219354; c=relaxed/simple; bh=TeZ9N8J9PP/jK4Ps9NCPMXrPdNzXJJmRc9mQkxGIDXM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=poLhj7l5CnvKJ508MKOmWOfnZ6UFFBVhCabKmEm31S55Tij9JYrAgOo9spoKCugstmUIye65zlgRe/qas7rDFdNX6DhKEPnrSg5+r39MF/CXwMxvbYC/8wADBqNP+fkamn+V64BjAoImZaoDpqeCBdScnd2FG9v1MLd4liny768= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SeYhyZQH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="SeYhyZQH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0190EC4CEF1; Tue, 26 Aug 2025 14:42:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756219354; bh=TeZ9N8J9PP/jK4Ps9NCPMXrPdNzXJJmRc9mQkxGIDXM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SeYhyZQHjfs8wQd40+boclPfNrPWbKvQC68xok/XvjFIyYOrzofV66ehhCFaweAD4 fnKprOWSYaGGzdt8EH2TYEwF9FLvxsrIbR4h7cg8pAP+Uru/8EYEf209WVtiZZY2QV UwOY8CA8iE0XVzYNAOXo46FGlJMuAa5fN/3+A18I= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dave Hansen , Chao Gao , Alison Schofield , "Peter Zijlstra (Intel)" , Sasha Levin Subject: [PATCH 5.4 348/403] x86/fpu: Delay instruction pointer fixup until after warning Date: Tue, 26 Aug 2025 13:11:14 +0200 Message-ID: <20250826110916.486731950@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250826110905.607690791@linuxfoundation.org> References: <20250826110905.607690791@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dave Hansen [ Upstream commit 1cec9ac2d071cfd2da562241aab0ef701355762a ] Right now, if XRSTOR fails a console message like this is be printed: Bad FPU state detected at restore_fpregs_from_fpstate+0x9a/0x170, reinitializing FPU registers. However, the text location (...+0x9a in this case) is the instruction *AFTER* the XRSTOR. The highlighted instruction in the "Code:" dump also points one instruction late. The reason is that the "fixup" moves RIP up to pass the bad XRSTOR and keep on running after returning from the #GP handler. But it does this fixup before warning. The resulting warning output is nonsensical because it looks like the non-FPU-related instruction is #GP'ing. Do not fix up RIP until after printing the warning. Do this by using the more generic and standard ex_handler_default(). Fixes: d5c8028b4788 ("x86/fpu: Reinitialize FPU registers if restoring FPU state fails") Signed-off-by: Dave Hansen Reviewed-by: Chao Gao Acked-by: Alison Schofield Acked-by: Peter Zijlstra (Intel) Cc:stable@vger.kernel.org Link: https://lore.kernel.org/all/20250624210148.97126F9E%40davehans-spike.ostc.intel.com [ adapted ex_handler_default() call ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/x86/mm/extable.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -59,13 +59,12 @@ __visible bool ex_handler_fprestore(cons unsigned long error_code, unsigned long fault_addr) { - regs->ip = ex_fixup_addr(fixup); - WARN_ONCE(1, "Bad FPU state detected at %pB, reinitializing FPU registers.", (void *)instruction_pointer(regs)); __copy_kernel_to_fpregs(&init_fpstate, -1); - return true; + + return ex_handler_default(fixup, regs, trapnr, error_code, fault_addr); } EXPORT_SYMBOL_GPL(ex_handler_fprestore);