From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 C7BF737881A for ; Wed, 29 Apr 2026 15:24:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777476287; cv=none; b=L/npjp9gwuWIqygahy7W7ilRFuufhXMIcTD36veVSX9ieU7oCGfFfE2JOEsA6zlaUO2lnrmrW8brTT57B+2vLs09otm9AfF2XBns09gghVU6V1szcGvt5ORbvVQvkoCXWBPP4e6J/DosXySW1Em8vfBxDwtEm2zD+zI9GEwFXlg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777476287; c=relaxed/simple; bh=jTx+THxx2aXF7hL7UE4UgFKEQQ3AvKKmFVMBT+G5Og4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=X0BjzPD9cuE8FSim+X7DhAmhuuQa+0DHxlanGVF1fjLbg76TGfdY0LMA4ghEGofBxXKxGkCA3hCArIfLF7xVUASSnAsbml35YHsR5s7HCSY6hcznCRX66GYY81Ie6r3RIaIDk4JXcUHite5w5e/LM58KiM8VdCT49QMdC3CYK9Q= 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=CaiSu+Nc; arc=none smtp.client-ip=170.10.133.124 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="CaiSu+Nc" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1777476285; 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=ZAXYezcr0Iy1hB7ntqgzjazz7eZ4Gyavm9fB/UWyNQQ=; b=CaiSu+Nce63Kzlu/BrEjKx0dfvNEJKiHc+dF0V5pk7O6VNRzLfr8j3d9fboy8KR4ZMGasN 3P7wIMVwV6WU5BcPyHtfAKc9cjdUYlSMnjfvZfbOYaUlefHW3EUkCe5jAcaOnqAknVYwuc qxkf2DqcmrYnNFz9d6wo8VL9fSSG9ak= 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-540-JepyDPiiNe-cYpKsZOgmKg-1; Wed, 29 Apr 2026 11:24:41 -0400 X-MC-Unique: JepyDPiiNe-cYpKsZOgmKg-1 X-Mimecast-MFC-AGG-ID: JepyDPiiNe-cYpKsZOgmKg_1777476277 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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 03E3A1800451; Wed, 29 Apr 2026 15:24:36 +0000 (UTC) Received: from fedora (unknown [10.44.48.22]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id D6F7A180045E; Wed, 29 Apr 2026 15:24:26 +0000 (UTC) Received: by fedora (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Wed, 29 Apr 2026 17:24:35 +0200 (CEST) Date: Wed, 29 Apr 2026 17:24:25 +0200 From: Oleg Nesterov To: "David Hildenbrand (Arm)" Cc: Darko Tominac , Masami Hiramatsu , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , Andrew Morton , "Liam R. Howlett" , Lorenzo Stoakes , Vlastimil Babka , Jann Horn , xe-linux-external@cisco.com, danielwa@cisco.com, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] mm/madvise: preserve uprobe breakpoints across MADV_DONTNEED Message-ID: References: <20260429131522.4049054-1-dtominac@cisco.com> <889e4186-9f75-45d3-bd9a-1c90b218a635@kernel.org> Precedence: bulk X-Mailing-List: linux-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: <889e4186-9f75-45d3-bd9a-1c90b218a635@kernel.org> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 On 04/29, David Hildenbrand (Arm) wrote: > > On 4/29/26 15:15, Darko Tominac wrote: > > > uprobe infrastructure does not re-instrument pages on individual page > > faults (uprobe_mmap() is only called during VMA creation, not on > > page-in), the breakpoints are silently lost once the discarded pages are > > re-read from the backing file. The probes stop firing with no error > > indication, and the only recovery is to unregister and re-register the > > affected uprobes. > > Right. Don't MADV_DONTNEED uprobes, just like you are not supposed to > MADV_DONTNEED debugger breakpoints/set data etc. :) Agreed, thanks. Oleg.