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 948553D3309 for ; Thu, 5 Feb 2026 12:29:44 +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=1770294584; cv=none; b=kUOZpY5K0pQiM4N5bAoWgPkkCpArtP379bS/ic1ktz2FmRF5nU3wuny6WM7OrBglMWeaVDK+dYqq3aLDsYmoU6s6ZoXJqsI8uWhc7QxHgGPboJNNoZxerRUQWDtMVWgJYdWkAS0SLPvUmCtpVIbANd+lorsm8UINuwnm2lr4XhI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770294584; c=relaxed/simple; bh=SmGwsreFC875e2XkP97W/boxhAVimJd+kAYCDyQkBOE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cSbj8MTh3eZQzrvf6O0m5/z1H0HLFJu8XapeRfheTYkshMuazQDKHJGdfwbq3d+D+Q/Q1rIvgng6e1PCfb2urVwkijFwuYp0GE7hY7rO4VyfPV3k2dePGeeqV0h61iu+CCGxoGJH3dkBX0tnmT8Zj0b6yfp+jDXPotDVPgjW/Nk= 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=Ln5Jah7R; 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="Ln5Jah7R" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1770294583; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SmGwsreFC875e2XkP97W/boxhAVimJd+kAYCDyQkBOE=; b=Ln5Jah7R4AcYDYRr/vvwWEOY1vXM9L67CfwltrLkKBEQ3LMqr3+hkSmZoyiy4VNJxoWcKc zNFT7+3u7FpmsG4xag1w+Dbi4lfZ4RXjdcn+zZXPXERLkF98NkiF74W/fqTpuRZiBY3t+j KIE7J1xCVkByiM580N4h2i6QWBq1zro= Received: from mx-prod-mc-08.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-537-1-HKa2yFP1ChMu5ZPDHAUg-1; Thu, 05 Feb 2026 07:29:40 -0500 X-MC-Unique: 1-HKa2yFP1ChMu5ZPDHAUg-1 X-Mimecast-MFC-AGG-ID: 1-HKa2yFP1ChMu5ZPDHAUg_1770294578 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (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-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id F127E1800473; Thu, 5 Feb 2026 12:29:37 +0000 (UTC) Received: from fedora (unknown [10.45.224.8]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id B9532300DDA1; Thu, 5 Feb 2026 12:29:31 +0000 (UTC) Received: by fedora (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Thu, 5 Feb 2026 13:29:37 +0100 (CET) Date: Thu, 5 Feb 2026 13:29:30 +0100 From: Oleg Nesterov To: Peter Zijlstra Cc: Carlos =?iso-8859-1?Q?L=F3pez?= , linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Masami Hiramatsu , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , "open list:UPROBES" Subject: Re: [PATCH] uprobes: replace deprecated kmap_atomic() with kmap_local_page() Message-ID: References: <20260205105725.298340-1-clopez@suse.de> <20260205111208.GK232055@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260205111208.GK232055@noisy.programming.kicks-ass.net> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 On 02/05, Peter Zijlstra wrote: > > On Thu, Feb 05, 2026 at 11:57:25AM +0100, Carlos López wrote: > > kmap_atomic() has been deprecated for a few years, and kmap_local_page() > > should be used instead, so replace it. Since the uprobes code relied on > > kmap_atomic() disabling page faults to access user pages, add the > > required calls to keep the existing behavior. > > Are those pagefault_disable()s really needed here, or is this just > cargo-culting? No, I think there are not needed. And the (already in tip) patches from Keke do not add pagefault_disable(). is_trap_at_addr() does pagefault_disable() because it is called with mm->mmap_lock held. Oleg.