Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751162AbdFCGrb (ORCPT ); Sat, 3 Jun 2017 02:47:31 -0400 Received: from mail-pf0-f174.google.com ([209.85.192.174]:35004 "EHLO mail-pf0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750753AbdFCGr3 (ORCPT ); Sat, 3 Jun 2017 02:47:29 -0400 MIME-Version: 1.0 In-Reply-To: <20170603062009.GI6365@ZenIV.linux.org.uk> References: <20170603011241.GH6365@ZenIV.linux.org.uk> <20170603062009.GI6365@ZenIV.linux.org.uk> From: Khazhismel Kumykov Date: Fri, 2 Jun 2017 23:47:27 -0700 Message-ID: Subject: Re: Hang/soft lockup in d_invalidate with simultaneous calls To: Al Viro Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Miklos Szeredi Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="94eb2c12591abd5615055108a437" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7378 Lines: 104 --94eb2c12591abd5615055108a437 Content-Type: text/plain; charset="UTF-8" On Fri, Jun 2, 2017 at 11:20 PM, Al Viro wrote: > The thing is, unlike shrink_dcache_parent() we *can* bugger off as > soon as we'd found no victims, nothing mounted and dentry itself > is unhashed. We can't do anything in select_collect() (we would've > broken shrink_dcache_parent() that way), but we can do unhashing > in check_and_drop() in "really nothing to do" case and we can return > from d_invalidate() after that. So how about this: That does the trick. --94eb2c12591abd5615055108a437 Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIIS5wYJKoZIhvcNAQcCoIIS2DCCEtQCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg ghBNMIIEXDCCA0SgAwIBAgIOSBtqDm4P/739RPqw/wcwDQYJKoZIhvcNAQELBQAwZDELMAkGA1UE BhMCQkUxGTAXBgNVBAoTEEdsb2JhbFNpZ24gbnYtc2ExOjA4BgNVBAMTMUdsb2JhbFNpZ24gUGVy c29uYWxTaWduIFBhcnRuZXJzIENBIC0gU0hBMjU2IC0gRzIwHhcNMTYwNjE1MDAwMDAwWhcNMjEw NjE1MDAwMDAwWjBMMQswCQYDVQQGEwJCRTEZMBcGA1UEChMQR2xvYmFsU2lnbiBudi1zYTEiMCAG A1UEAxMZR2xvYmFsU2lnbiBIViBTL01JTUUgQ0EgMTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCC AQoCggEBALR23lKtjlZW/17kthzYcMHHKFgywfc4vLIjfq42NmMWbXkNUabIgS8KX4PnIFsTlD6F GO2fqnsTygvYPFBSMX4OCFtJXoikP2CQlEvO7WooyE94tqmqD+w0YtyP2IB5j4KvOIeNv1Gbnnes BIUWLFxs1ERvYDhmk+OrvW7Vd8ZfpRJj71Rb+QQsUpkyTySaqALXnyztTDp1L5d1bABJN/bJbEU3 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