From nobody Sun Nov 24 00:05:54 2024 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 7853615853B; Mon, 11 Nov 2024 12:54:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731329678; cv=none; b=jLnuK1htfIjprsxY3/fs27yI81SeFNg06Mc/SCr2FzylImBcxZqIFjimqt1D59WIJ/skL5mxqg2FxbfsvrjSjRV60bsMTwlrXbyoXKGZ9cNj8pcojxHMexFFSg0SQMMH94zXMyoK5hfi4KellEpLf6APzf5gH8ZpUvD9WnO+CkI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731329678; c=relaxed/simple; bh=re7YlqIlSiYJgwFG46YU4SbL85meBq6Fe4HTgqcFdvk=; h=Message-Id:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=QfKa9jnJsBihnKM9g8/LdOe71RERj6FmiNdbfcM7Qhai0vxcVuJKkIZoXuPPlbCBZNG+K5aqzSx62bAQmthfYrUXHa9LvatrGunvFFtbB+irSysoRtlMt7BwQnzFE5yIINix3d8rRUwzTmfDRb5FDlyiRQLkYgDGMPaZeoIGYzI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=ibVwk2A9; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ibVwk2A9" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-Id:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=5G7tZh92XjzM00TzgErAKrW0ED3Ua0OvGoNXzUhcSY0=; b=ibVwk2A9uRdQ5Dm4vPQYhrvld0 L4VN0NGeWV0uHk24mDyhPoyF2y7YF6XhDybzQj/2zpEyqUgMYAv1KFMNpWCYayl+MLRsmBgNQkmSQ Pa9OY6HyVG3Oh79AuiMtkomYkteCcvz6gEcVNPresdIqJpZYjJE1FVfFAgmFz3NH5JBqkEwjx1mX3 +E9gANxKibfLsdY0fXtEwOk3BBb9tKlxggcBepR5VFEHnitlfywbFbKQqRkd5YlUvHKvquzl4u4cK KqDn8C+UOYarHprqt9AOxC2A0B3thkqtQa4axNRbob2iIFSxNOFEIEbA/qzD6D+SU0kb8gG1HR5Qz 3ejlvmIg==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.98 #2 (Red Hat Linux)) id 1tATwA-0000000Coer-207x; Mon, 11 Nov 2024 12:54:34 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 0) id E56AB3021DA; Mon, 11 Nov 2024 13:54:32 +0100 (CET) Message-Id: <20241111125219.033699387@infradead.org> User-Agent: quilt/0.65 Date: Mon, 11 Nov 2024 12:59:44 +0100 From: Peter Zijlstra To: seanjc@google.com, pbonzini@redhat.com, jpoimboe@redhat.com, tglx@linutronix.de Cc: linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org, jthoughton@google.com, "Peter Zijlstra (Intel)" Subject: [PATCH v2 09/12] x86/nospec: JMP_NOSPEC References: <20241111115935.796797988@infradead.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/include/asm/nospec-branch.h | 32 ++++++++++++++++++++++++++++++= ++ 1 file changed, 32 insertions(+) --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -403,6 +403,17 @@ static inline void call_depth_return_thu "call *%[thunk_target]\n", \ X86_FEATURE_RETPOLINE_LFENCE) =20 +# define JMP_NOSPEC \ + ALTERNATIVE_2( \ + ANNOTATE_RETPOLINE_SAFE \ + "jmp *%[thunk_target]\n", \ + "jmp __x86_indirect_thunk_%V[thunk_target]\n", \ + X86_FEATURE_RETPOLINE, \ + "lfence;\n" \ + ANNOTATE_RETPOLINE_SAFE \ + "jmp *%[thunk_target]\n", \ + X86_FEATURE_RETPOLINE_LFENCE) + # define THUNK_TARGET(addr) [thunk_target] "r" (addr) =20 #else /* CONFIG_X86_32 */ @@ -433,10 +444,31 @@ static inline void call_depth_return_thu "call *%[thunk_target]\n", \ X86_FEATURE_RETPOLINE_LFENCE) =20 +# define JMP_NOSPEC \ + ALTERNATIVE_2( \ + ANNOTATE_RETPOLINE_SAFE \ + "jmp *%[thunk_target]\n", \ + " jmp 901f;\n" \ + " .align 16\n" \ + "901: call 903f;\n" \ + "902: pause;\n" \ + " lfence;\n" \ + " jmp 902b;\n" \ + " .align 16\n" \ + "903: lea 4(%%esp), %%esp;\n" \ + " pushl %[thunk_target];\n" \ + " ret;\n", \ + X86_FEATURE_RETPOLINE, \ + "lfence;\n" \ + ANNOTATE_RETPOLINE_SAFE \ + "jmp *%[thunk_target]\n", \ + X86_FEATURE_RETPOLINE_LFENCE) + # define THUNK_TARGET(addr) [thunk_target] "rm" (addr) #endif #else /* No retpoline for C / inline asm */ # define CALL_NOSPEC "call *%[thunk_target]\n" +# define JMP_NOSPEC "jmp *%[thunk_target]\n" # define THUNK_TARGET(addr) [thunk_target] "rm" (addr) #endif