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 4C7A322F389 for ; Wed, 13 Aug 2025 16:42:21 +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=1755103342; cv=none; b=DNvcGBdRGxFUURxpThP14y37G9d0A8M/NQETFQp5R5Rj+BuRd5fEkTOwPeqIc+hM1Umh3NQDVKBwbr0P/bNWG480WJdQ5E81VCW45w+5HVjkPJoOtVHcGYFLPktJEDKaHcKV+EE4wNYwgd92uCVP2WnNtNuyh7AIrdJxcTeedS8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755103342; c=relaxed/simple; bh=d6SiTJ2gPPy7G0mF3ymCpTx9GLLSlFcB78dVhbHCsCA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=lYfX9jgGOqrHZIHTVuY+haOQBNYYr3En2jExdzSHHkaqTu3dWxM5yaSwJ5KsbZboqHqdKO65WCSmgPkjASfcwE9Q4pJUNYV6J9vG4pk7ejKTXSknhnBvSs90wKsPfogEVNATRtQI1XjyzPRbuabz1JngkWi2aCAgDYClxe9mPkc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=MLS9tCBm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="MLS9tCBm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1F324C4CEEB; Wed, 13 Aug 2025 16:42:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755103341; bh=d6SiTJ2gPPy7G0mF3ymCpTx9GLLSlFcB78dVhbHCsCA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MLS9tCBm65Cao2Myml8WGKHH6TXYKM60JeuwtbmSW4pyk/3gma8i69bNv2ekrP6ym 5bgPtW5intn58V9eR6/F3GZmIl2wu/7nz21aikUgzxPHxLgA07s2pR/2SVW85p3FS3 if//CezUYG1Mv1zsnjyiF+92ty9t9EErV4+QECqyXig4XBUKo6ipF5rOHgial/4B8z LoZGLudT4o1VMzHbCLnrulYL1CUMlUvnfSflEI82PN7rzaFdCabzUoCcvSAzX0atVQ DUgMir5x2GoTkULN95Rd8tpGSEBSHS3CNevC2l3SaQy9BR6lpEvHPNgsoCXawQ2K8O i6X/Bcko53/0A== From: Sasha Levin To: stable@vger.kernel.org Cc: Dave Hansen , Chao Gao , Alison Schofield , Peter Zijlstra , Sasha Levin Subject: [PATCH 5.4.y] x86/fpu: Delay instruction pointer fixup until after warning Date: Wed, 13 Aug 2025 12:42:19 -0400 Message-Id: <20250813164219.2063341-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <2025081252-serotonin-cranium-3e92@gregkh> References: <2025081252-serotonin-cranium-3e92@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 --- arch/x86/mm/extable.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c index 30bb0bd3b1b8..ae7e056d0007 100644 --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -59,13 +59,12 @@ __visible bool ex_handler_fprestore(const struct exception_table_entry *fixup, 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); -- 2.39.5