Received: by 2002:a05:6a10:f3d0:0:0:0:0 with SMTP id a16csp3502564pxv; Mon, 12 Jul 2021 19:43:31 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxZBvPTKpiWB94gEjAPb0OU9uGUxd4MeyFQR5S9i3LPv/8J0Xx5gYOAtJqgHjgEtiVVNIj5 X-Received: by 2002:a17:907:76da:: with SMTP id kf26mr2617100ejc.511.1626144211533; Mon, 12 Jul 2021 19:43:31 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1626144211; cv=none; d=google.com; s=arc-20160816; b=mm02jCXQrtHM01aIYARUPZGzrI4QdlifQryTZ8cTBNGiDQiaH+TyPCjWjO6ujwbQYn b7NL9rSKT6MUrUwX2t9luPiCKcw9S+TqaBi3UyadpV/pgFFP69enu4TnVtUpzCQVZS0G dUkxNWHIBdhrgb/lU9jEGHH48NvCGvFIlzGJGSvErMM6J+xfZEw9msKlO2p4UJmo8nRh MDTxcrIFNaOPi5h2KQT8Cv2UwUY59/igSEf0WsohdlcI/gX/dTLWyQlxIc2akF0/byBm rp5dDUSTRvwNxf+FNmRrega5PcIUSRDNTHcvJcQz6KnzwTs6ng/38Bvwr412c1SIgF5j B02g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:date:cc:to:from:subject:message-id :dkim-signature; bh=q802Vv2CMSQW17WNtOwOhY0YLtlaJIPW7BobIkTXRD8=; b=J+XM0M/yqCQKqFTm/MeDkY/uhMofgmFU2fwYtKNioUGzFbP5U75BDtfI7TSwD6IfMb Jq6qM/7Wvd1UHXxHMoKiJIe1KKXlZrfC1ZQsFeefY5N50tAZW1gA+LXwP9iYLJTRdXRd E/PkpcX/V9ArRQXwglKWGgZDt3eCkA2IZ8xU4N284j9LEXpzPo4V/u1cA2WhaOK0GxAY k80PQiqDxXn4EkSK8JJfbVM6RwXQ+yF8CQ1ZayqziuoCBzp9VYRJZS6eKfOy31w0JyIi n5PTTPM/NpMvgIe75IoeTfoMgi2n91NeMc2qYm2BtBb5Em6nyrkvDVpvSuRA/0dd0stA V4IQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@mediatek.com header.s=dk header.b=hx90P2w5; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=mediatek.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id c7si18914341ejc.177.2021.07.12.19.43.08; Mon, 12 Jul 2021 19:43:31 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@mediatek.com header.s=dk header.b=hx90P2w5; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=mediatek.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233939AbhGMCpE (ORCPT + 99 others); Mon, 12 Jul 2021 22:45:04 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:56374 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S233444AbhGMCpD (ORCPT ); Mon, 12 Jul 2021 22:45:03 -0400 X-UUID: d346211ecf4a4bbdb4686e1c9680087b-20210713 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:MIME-Version:Content-Type:References:In-Reply-To:Date:CC:To:From:Subject:Message-ID; bh=q802Vv2CMSQW17WNtOwOhY0YLtlaJIPW7BobIkTXRD8=; b=hx90P2w5iFarKf38iFgJqSy0FW8RKT3/GWSsc6BIiS0gIrdB98DfcfZD5LiK2h+3xv++0BsBZ4JumK0I1l4NLrdeLyZqMKMvmPVHDxINR0cpZ8F7l/DLfP2lfeYr6Rdgs6zkXkbbLl/FvsxZxMl34rc2FvfUCYlrcQsk6S95cFI=; X-UUID: d346211ecf4a4bbdb4686e1c9680087b-20210713 Received: from mtkexhb02.mediatek.inc [(172.21.101.103)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1800056760; Tue, 13 Jul 2021 10:42:10 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs02n2.mediatek.inc (172.21.101.101) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 13 Jul 2021 10:42:08 +0800 Received: from mtksdccf07 (172.21.84.99) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 13 Jul 2021 10:42:09 +0800 Message-ID: <1fabb91167a86990f4723e9036a0e006293518f4.camel@mediatek.com> Subject: Re: [PATCH] [fuse] alloc_page nofs avoid deadlock From: Ed Tsai To: Miklos Szeredi CC: , , chenguanyou , chenguanyou , Date: Tue, 13 Jul 2021 10:42:09 +0800 In-Reply-To: References: <20210603125242.31699-1-chenguanyou@xiaomi.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.2 MIME-Version: 1.0 X-MTK: N Content-Transfer-Encoding: base64 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org T24gVHVlLCAyMDIxLTA2LTA4IGF0IDE3OjMwICswMjAwLCBNaWtsb3MgU3plcmVkaSB3cm90ZToN Cj4gT24gVGh1LCAzIEp1biAyMDIxIGF0IDE0OjUyLCBjaGVuZ3VhbnlvdSA8Y2hlbmd1YW55b3U5 MzM4QGdtYWlsLmNvbT4NCj4gd3JvdGU6DQo+ID4gDQo+ID4gQUJBIGRlYWRsb2NrDQo+ID4gDQo+ ID4gUElEOiAxNzE3MiBUQVNLOiBmZmZmZmZjMGMxNjJjMDAwIENQVTogNiBDT01NQU5EOiAiVGhy ZWFkLTIxIg0KPiA+IDAgW2ZmZmZmZjgwMmQxNmI0MDBdIF9fc3dpdGNoX3RvIGF0IGZmZmZmZjgw MDgwODZhNGMNCj4gPiAxIFtmZmZmZmY4MDJkMTZiNDcwXSBfX3NjaGVkdWxlIGF0IGZmZmZmZjgw MDkxZmZlNTgNCj4gPiAyIFtmZmZmZmY4MDJkMTZiNGQwXSBzY2hlZHVsZSBhdCBmZmZmZmY4MDA5 MjAwMzQ4DQo+ID4gMyBbZmZmZmZmODAyZDE2YjRmMF0gYml0X3dhaXQgYXQgZmZmZmZmODAwOTIw MTA5OA0KPiA+IDQgW2ZmZmZmZjgwMmQxNmI1MTBdIF9fd2FpdF9vbl9iaXQgYXQgZmZmZmZmODAw OTIwMGEzNA0KPiA+IDUgW2ZmZmZmZjgwMmQxNmI1YjBdIGlub2RlX3dhaXRfZm9yX3dyaXRlYmFj ayBhdCBmZmZmZmY4MDA4MzBlMWU4DQo+ID4gNiBbZmZmZmZmODAyZDE2YjVlMF0gZXZpY3QgYXQg ZmZmZmZmODAwODJmYjE1Yw0KPiA+IDcgW2ZmZmZmZjgwMmQxNmI2MjBdIGlwdXQgYXQgZmZmZmZm ODAwODJmOTI3MA0KPiA+IDggW2ZmZmZmZjgwMmQxNmI2ODBdIGRlbnRyeV91bmxpbmtfaW5vZGUg YXQgZmZmZmZmODAwODJmNGM5MA0KPiA+IDkgW2ZmZmZmZjgwMmQxNmI2YTBdIF9fZGVudHJ5X2tp bGwgYXQgZmZmZmZmODAwODJmMTcxMA0KPiA+IDEwIFtmZmZmZmY4MDJkMTZiNmQwXSBzaHJpbmtf ZGVudHJ5X2xpc3QgYXQgZmZmZmZmODAwODJmMWMzNA0KPiA+IDExIFtmZmZmZmY4MDJkMTZiNzUw XSBwcnVuZV9kY2FjaGVfc2IgYXQgZmZmZmZmODAwODJmMThhOA0KPiA+IDEyIFtmZmZmZmY4MDJk MTZiNzcwXSBzdXBlcl9jYWNoZV9zY2FuIGF0IGZmZmZmZjgwMDgyZDU1YWMNCj4gPiAxMyBbZmZm ZmZmODAyZDE2Yjg2MF0gc2hyaW5rX3NsYWIgYXQgZmZmZmZmODAwODI2NjE3MA0KPiA+IDE0IFtm ZmZmZmY4MDJkMTZiOTAwXSBzaHJpbmtfbm9kZSBhdCBmZmZmZmY4MDA4MjZiNDIwDQo+ID4gMTUg W2ZmZmZmZjgwMmQxNmI5ODBdIGRvX3RyeV90b19mcmVlX3BhZ2VzIGF0IGZmZmZmZjgwMDgyNjg0 NjANCj4gPiAxNiBbZmZmZmZmODAyZDE2YmE2MF0gdHJ5X3RvX2ZyZWVfcGFnZXMgYXQgZmZmZmZm ODAwODI2ODBkMA0KPiA+IDE3IFtmZmZmZmY4MDJkMTZiYmUwXSBfX2FsbG9jX3BhZ2VzX25vZGVt YXNrIGF0IGZmZmZmZjgwMDgyNTY1MTQNCj4gPiAxOCBbZmZmZmZmODAyZDE2YmM2MF0gZnVzZV9j b3B5X2ZpbGwgYXQgZmZmZmZmODAwODQzODI2OA0KPiA+IDE5IFtmZmZmZmY4MDJkMTZiZDAwXSBm dXNlX2Rldl9kb19yZWFkIGF0IGZmZmZmZjgwMDg0Mzc2NTQNCj4gPiAyMCBbZmZmZmZmODAyZDE2 YmRjMF0gZnVzZV9kZXZfc3BsaWNlX3JlYWQgYXQgZmZmZmZmODAwODQzNmY0MA0KPiA+IDIxIFtm ZmZmZmY4MDJkMTZiZTYwXSBzeXNfc3BsaWNlIGF0IGZmZmZmZjgwMDgzMTVkMTgNCj4gPiAyMiBb ZmZmZmZmODAyZDE2YmZmMF0gX19zeXNfdHJhY2UgYXQgZmZmZmZmODAwODA4NDAxNA0KPiA+IA0K PiA+IFBJRDogOTY1MiBUQVNLOiBmZmZmZmZjMGM5Y2UwMDAwIENQVTogNCBDT01NQU5EOiAia3dv cmtlci91MTY6OCINCj4gPiAwIFtmZmZmZmY4MDJlNzkzNjUwXSBfX3N3aXRjaF90byBhdCBmZmZm ZmY4MDA4MDg2YTRjDQo+ID4gMSBbZmZmZmZmODAyZTc5MzZjMF0gX19zY2hlZHVsZSBhdCBmZmZm ZmY4MDA5MWZmZTU4DQo+ID4gMiBbZmZmZmZmODAyZTc5MzcyMF0gc2NoZWR1bGUgYXQgZmZmZmZm ODAwOTIwMDM0OA0KPiA+IDMgW2ZmZmZmZjgwMmU3OTM3NzBdIF9fZnVzZV9yZXF1ZXN0X3NlbmQg YXQgZmZmZmZmODAwODQzNTc2MA0KPiA+IDQgW2ZmZmZmZjgwMmU3OTM3YjBdIGZ1c2Vfc2ltcGxl X3JlcXVlc3QgYXQgZmZmZmZmODAwODQzNWIxNA0KPiA+IDUgW2ZmZmZmZjgwMmU3OTM5MzBdIGZ1 c2VfZmx1c2hfdGltZXMgYXQgZmZmZmZmODAwODQzYTdhMA0KPiA+IDYgW2ZmZmZmZjgwMmU3OTM5 NTBdIGZ1c2Vfd3JpdGVfaW5vZGUgYXQgZmZmZmZmODAwODQzZTRkYw0KPiA+IDcgW2ZmZmZmZjgw MmU3OTM5ODBdIF9fd3JpdGViYWNrX3NpbmdsZV9pbm9kZSBhdCBmZmZmZmY4MDA4MzEyNzQwDQo+ ID4gOCBbZmZmZmZmODAyZTc5M2FhMF0gd3JpdGViYWNrX3NiX2lub2RlcyBhdCBmZmZmZmY4MDA4 MzExN2U0DQo+ID4gOSBbZmZmZmZmODAyZTc5M2IwMF0gX193cml0ZWJhY2tfaW5vZGVzX3diIGF0 IGZmZmZmZjgwMDgzMTFkOTgNCj4gPiAxMCBbZmZmZmZmODAyZTc5M2MwMF0gd2Jfd3JpdGViYWNr IGF0IGZmZmZmZjgwMDgzMTBjZmMNCj4gPiAxMSBbZmZmZmZmODAyZTc5M2QwMF0gd2Jfd29ya2Zu IGF0IGZmZmZmZjgwMDgzMGU0YTgNCj4gPiAxMiBbZmZmZmZmODAyZTc5M2Q5MF0gcHJvY2Vzc19v bmVfd29yayBhdCBmZmZmZmY4MDA4MGU0ZmFjDQo+ID4gMTMgW2ZmZmZmZjgwMmU3OTNlMDBdIHdv cmtlcl90aHJlYWQgYXQgZmZmZmZmODAwODBlNTY3MA0KPiA+IDE0IFtmZmZmZmY4MDJlNzkzZTYw XSBrdGhyZWFkIGF0IGZmZmZmZjgwMDgwZWI2NTANCj4gDQo+IFRoZSBpc3N1ZSBpcyByZWFsLg0K PiANCj4gVGhlIGZpeCwgaG93ZXZlciwgaXMgbm90IHRoZSByaWdodCBvbmUuICBUaGUgZnVuZGFt ZW50YWwgcHJvYmxlbSBpcw0KPiB0aGF0IGZ1c2Vfd3JpdGVfaW5vZGUoKSBibG9ja3Mgb24gYSBy ZXF1ZXN0IHRvIHVzZXJzcGFjZS4NCj4gDQo+IFRoaXMgaXMgdGhlIHNhbWUgaXNzdWUgdGhhdCBm dXNlX3dyaXRlcGFnZS9mdXNlX3dyaXRlcGFnZXMgZmFjZS4gIEluDQo+IHRoYXQgY2FzZSB0aGUg c29sdXRpb24gd2FzIHRvIGNvcHkgdGhlIHBhZ2UgY29udGVudHMgdG8gYSB0ZW1wb3JhcnkNCj4g YnVmZmVyIGFuZCByZXR1cm4gaW1tZWRpYXRlbHkgYXMgaWYgdGhlIHdyaXRlYmFjayBhbHJlYWR5 IGNvbXBsZXRlZC4NCj4gDQo+IFNvbWV0aGluZyBzaW1pbGFyIG5lZWRzIHRvIGJlIGRvbmUgaGVy ZTogc2VuZCB0aGUgRlVTRV9TRVRBVFRSDQo+IHJlcXVlc3QNCj4gYXN5bmNocm9ub3VzbHkgYW5k IHJldHVybiBpbW1lZGlhdGVseSBmcm9tIGZ1c2Vfd3JpdGVfaW5vZGUoKS4gIFRoZQ0KPiB0cmlj a3kgcGFydCBpcyB0byBtYWtlIHN1cmUgdGhhdCBtdWx0aXBsZSB0aW1lIHVwZGF0ZXMgZm9yIHRo ZSBzYW1lDQo+IGlub2RlIGFyZW4ndCBtaXhlZCB1cC4uLg0KPiANCj4gVGhhbmtzLA0KPiBNaWts b3MNCg0KRGVhciBTemVyZWRpLA0KDQpXcml0ZWJhY2sgdGhyZWFkIGNhbGxzIGZ1c2Vfd3JpdGVf aW5vZGUoKSBhbmQgd2FpdCBmb3IgdXNlciBEYWVtb24gdG8NCmNvbXBsZXRlIHRoaXMgd3JpdGUg aW5vZGUgcmVxdWVzdC4gVGhlIHVzZXIgZGFlbW9uIHdpbGwgYWxsb2NfcGFnZSgpDQphZnRlciB0 YWtpbmcgdGhpcyByZXF1ZXN0LCBhbmQgYSBkZWFkbG9jayBjb3VsZCBoYXBwZW4gd2hlbiB3ZSB0 cnkgdG8NCnNocmluayBkZW50cnkgbGlzdCB1bmRlciBtZW1vcnkgcHJlc3N1cmUuDQoNCldlIChN ZWRpYXRlaykgZ2xhZCB0byB3b3JrIG9uIHRoaXMgaXNzdWUgZm9yIG1haW5saW5lIGFuZCBhbHNv IExUUy4gU28NCmFub3RoZXIgcHJvYmxlbSBpcyB0aGF0IHdlIHNob3VsZCBub3QgY2hhbmdlIHRo ZSBwcm90b2NvbCBvciBmZWF0dXJlDQpmb3Igc3RhYmxlIGtlcm5lbC4NCg0KVXNlIEdGUF9OT0ZT IHwgX19HRlBfSElHSE1FTSBjYW4gcmVhbGx5IGF2b2lkIHRoaXMgYnkgc2tpcCB0aGUgZGVudHJ5 DQpzaGlybmtlci4gSXQgd29ya3MgYnV0IGRlZ3JhZGUgdGhlIGFsbG9jX3BhZ2Ugc3VjY2VzcyBy YXRlLiBJbiBhIG1vcmUNCmZ1bmRhbWVudGFsIHdheSwgd2UgY291bGQgY2FjaGUgdGhlIGNvbnRl bnRzIGFuZCByZXR1cm4gaW1tZWRpYXRlbHkuDQpCdXQgaG93IHRvIGVuc3VyZSB0aGUgcmVxdWVz dCB3aWxsIGJlIGRvbmUgc3VjY2Vzc2Z1bGx5LCBlLmcuLCBhbHdheXMNCnJldHJ5IGlmIGl0IGZh aWxzIGZyb20gZGFlbW9uLg0KDQoNCg==