From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 ADCD42367BA for ; Fri, 11 Apr 2025 12:48:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744375738; cv=none; b=VTiYluPlO7c090dSN56MkcpYF3UGwdIeVfIihebmx/d6TIE5qAppMzG1CSSzAjUcJUYXRxyOzEoJDBY39WN0Yd1n2ihJHIqFkts18xAz5GiPts+xx0GxgIeriOg2GjWdkpuZbYnJUPipalACE32yhSIJZQKLcvolJgHtucjCuiU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744375738; c=relaxed/simple; bh=BcC98ws7X2rPc51yx5q6n6PNb7iZ49cCMtEKJk2Evo0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LgnhA6jw5J04j0/QJkhvkLDtz1+fkfHLj/RQc3HbuAlM+YoK5h7VMCu6oQJ0Ny3togfwpMM4tLv8D9ajXBI094/5bkua35Xd+2ZJ5R8wp8botvEpEVFdA1rX1m3thfqNWGqFduKi+Ae9vXQZVu64iwp8hRAHY6C7htcr1kWI1B0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=bPip5nOB; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bPip5nOB" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744375735; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=TrutyA31aFwEpX5Hu60jTx9GaJXm6qHgLzII0vBWWqU=; b=bPip5nOBCI3osRolK6spfE1ZBT89qGhl3v+CjR9b3wWbVKxtJv5fjaILShGg2ARTWMXw4z hLJfpQUsJw5vk3cBzpetqeVTVPLCcvaVgpTdjXveUlIuh5nsjV0daVheQSi4araGHoUUka 3tnQQeZv4blEaGjsOMCEbUopGfOyLxQ= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-449-9lGNpQCmNfK6zLJmOCGtyA-1; Fri, 11 Apr 2025 08:48:49 -0400 X-MC-Unique: 9lGNpQCmNfK6zLJmOCGtyA-1 X-Mimecast-MFC-AGG-ID: 9lGNpQCmNfK6zLJmOCGtyA_1744375727 Received: from mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.15]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B2E9F180025F; Fri, 11 Apr 2025 12:48:46 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.224.222]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id 714E71956094; Fri, 11 Apr 2025 12:48:40 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Fri, 11 Apr 2025 14:48:11 +0200 (CEST) Date: Fri, 11 Apr 2025 14:48:03 +0200 From: Oleg Nesterov To: Jiri Olsa Cc: Peter Zijlstra , Ingo Molnar , Andrii Nakryiko , bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, x86@kernel.org, Song Liu , Yonghong Song , John Fastabend , Hao Luo , Steven Rostedt , Masami Hiramatsu , Alan Maguire Subject: Re: [PATCHv2 perf/core 1/2] uprobes/x86: Add support to emulate nop instructions Message-ID: <20250411124802.GE5322@redhat.com> References: <20250411121756.567274-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250411121756.567274-1-jolsa@kernel.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 On 04/11, Jiri Olsa wrote: > > --- a/arch/x86/kernel/uprobes.c > +++ b/arch/x86/kernel/uprobes.c > @@ -840,6 +840,12 @@ static int branch_setup_xol_ops(struct arch_uprobe *auprobe, struct insn *insn) > insn_byte_t p; > int i; > > + /* x86_nops[i]; same as jmp with .offs = 0 */ > + for (i = 1; i <= ASM_NOP_MAX; ++i) { > + if (!memcmp(insn->kaddr, x86_nops[i], i)) > + goto setup; > + } Acked-by: Oleg Nesterov