From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 807D2CED26B for ; Tue, 8 Oct 2024 05:31:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=E27Re7NhbJ14fNZbR1r+m7uns/kLm3MfpiXgxf4rjCk=; b=XBynQ7NH5w/P2B5zJiou5rQnEV exwyljFqZe3xBbchhUHEUgI92eubi8UJhmCMkKazwZdOe/QdJUCNo39iekYXXtkwmjHVGm6d2jn1/ EH/M3i9tplODc6KaNOcEp9xOwIKNH38CmBoR/w/lpwZ7R/VPmDSliy1sK/EeXhQzNH9qbvxTDpShV 9VKatvT4W0utT6VCBVCyZZmpdv0SGrJuK03eMQDdu4X+cyGJ2R0O+mcXRLorlUveN4XIApsWBDiQc pLKLhKrqE7JK85vLXJUhBT0Fyl3E0bwLduVLlcQ5aRCMzDtOdra4ODT9jzdSd30qEbmrVdatWuRC1 t9iSOXuQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1sy2oc-00000004YaZ-3uYG; Tue, 08 Oct 2024 05:31:22 +0000 Received: from mail-pl1-x634.google.com ([2607:f8b0:4864:20::634]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1sy2oZ-00000004YZH-1c02 for linux-riscv@lists.infradead.org; Tue, 08 Oct 2024 05:31:21 +0000 Received: by mail-pl1-x634.google.com with SMTP id d9443c01a7336-20c544d34bcso2651845ad.1 for ; Mon, 07 Oct 2024 22:31:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1728365478; x=1728970278; darn=lists.infradead.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=YVWWt1mcV86CG5um5aUopa5TS6G5mg+pb0D64jrI0rI=; b=gtgv+10jCVJK7M0M/6IuT2T6B8LL1qXG53zhDB/4Zj4L41YUCVdJeXkyBUEBr10S8K GlZNJTh/mhFgpnBdK9eBfUPiXLyDDQ6eFcMK5BsPmEOfxEKlswWYuc9aOM5xPrK3KKjy h8OnAxmzAuv6+bnc5rEEhLJfL+eDkd5fT1lmdqA+Q9naAPvuJBGhroB0c/ziKJbECIqY rKZXCEtStKX63iji/EGqSiVU8CL8SmJWwBoyx188gBN6VmuprXG8N3xU4Cx2qoun+jam Pq6lw31I/hi3S6P+Tg2xLQySAZtOe5K2mdWKs6Cmf8Qi34ctUEms0T+bgUn/I3zE29Bw Dk3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728365478; x=1728970278; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=YVWWt1mcV86CG5um5aUopa5TS6G5mg+pb0D64jrI0rI=; b=YuWbPlbmo8w3ASjcuDBjOKCHQ5cWSDGu4mVT2/WBhyCMcrf4uwTrAyb5gwXtpagXPZ GFLfFrJNbzjxGTtDb8HnjpsqkT7vB3u2N7NpGbYN7TTig3vXmh3wP/nXkOo0+zTUuWmE bLdxa3rhxtBfiyQ5h56CJjAe+kctOguMBfnXg4D2AvuybbBtAwEiUYOKQEF+iaQb3SvO E7hmCl5ftqkFQ+m+np28mNXaIIMUD0eRJn933u0vWRVIHkPco8pMMkYNPeVmBqtzmKTs 5OEct7texMNtvRzp81mr80HtrUdjch8NyW9LkLnyGPL9nyLwmKWPoK/daU/TIyFGKimh 3KYw== X-Forwarded-Encrypted: i=1; AJvYcCXi4fwbgF2+vgT7RPV9rdZakwFPlKLw/qAJM2XsgOQPdSinGsWH0g/bU4tOeuJ4/jdh+R1BCLX9kxkHOA==@lists.infradead.org X-Gm-Message-State: AOJu0YxOC9BuoUqDFykgx8BYbpNzKAJiAqJf90QhhCdPdwzxz0pMilQN QG9TQGDB6a3uP6RPofJIwr85Re08QG2Ss5xkf2TxF89ug9wQQdfSAvhEcu8ae0A= X-Google-Smtp-Source: AGHT+IGthWcJ/4TKf5GSv621dnUUfPBgutAW7rucqDwxG39GX8eeue8mfmIeD0tAu25NcYxCwQyqlA== X-Received: by 2002:a17:902:d4cd:b0:20b:7731:e3f8 with SMTP id d9443c01a7336-20bfe00b926mr216344355ad.26.1728365478346; Mon, 07 Oct 2024 22:31:18 -0700 (PDT) Received: from debug.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-20c1393a292sm48470455ad.173.2024.10.07.22.31.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Oct 2024 22:31:18 -0700 (PDT) Date: Mon, 7 Oct 2024 22:31:14 -0700 From: Deepak Gupta To: Zong Li Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Lorenzo Stoakes , Paul Walmsley , Palmer Dabbelt , Albert Ou , Conor Dooley , Rob Herring , Krzysztof Kozlowski , Arnd Bergmann , Christian Brauner , Peter Zijlstra , Oleg Nesterov , Eric Biederman , Kees Cook , Jonathan Corbet , Shuah Khan , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, alistair.francis@wdc.com, richard.henderson@linaro.org, jim.shu@sifive.com, andybnac@gmail.com, kito.cheng@sifive.com, charlie@rivosinc.com, atishp@rivosinc.com, evan@rivosinc.com, cleger@rivosinc.com, alexghiti@rivosinc.com, samitolvanen@google.com, broonie@kernel.org, rick.p.edgecombe@intel.com Subject: Re: [PATCH 16/33] riscv/shstk: If needed allocate a new shadow stack on clone Message-ID: References: <20241001-v5_user_cfi_series-v1-0-3ba65b6e550f@rivosinc.com> <20241001-v5_user_cfi_series-v1-16-3ba65b6e550f@rivosinc.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241007_223119_743506_F04D9CE0 X-CRM114-Status: GOOD ( 30.79 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: base64 Content-Type: text/plain; charset="utf-8"; Format="flowed" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org T24gVHVlLCBPY3QgMDgsIDIwMjQgYXQgMDE6MTY6MTdQTSArMDgwMCwgWm9uZyBMaSB3cm90ZToK Pk9uIFR1ZSwgT2N0IDgsIDIwMjQgYXQgNzozMOKAr0FNIERlZXBhayBHdXB0YSA8ZGVidWdAcml2 b3NpbmMuY29tPiB3cm90ZToKPj4KPj4gT24gTW9uLCBPY3QgMDcsIDIwMjQgYXQgMDQ6MTc6NDdQ TSArMDgwMCwgWm9uZyBMaSB3cm90ZToKPj4gPk9uIFdlZCwgT2N0IDIsIDIwMjQgYXQgMTI6MjDi gK9BTSBEZWVwYWsgR3VwdGEgPGRlYnVnQHJpdm9zaW5jLmNvbT4gd3JvdGU6Cj4+ID4+Cj4+ID4+ IFVzZXJzcGFjZSBzcGVjaWZpZXMgQ0xPTkVfVk0gdG8gc2hhcmUgYWRkcmVzcyBzcGFjZSBhbmQg c3Bhd24gbmV3IHRocmVhZC4KPj4gPj4gYGNsb25lYCBhbGxvdyB1c2Vyc3BhY2UgdG8gc3BlY2lm eSBhIG5ldyBzdGFjayBmb3IgbmV3IHRocmVhZC4gSG93ZXZlcgo+PiA+PiB0aGVyZSBpcyBubyB3 YXkgdG8gc3BlY2lmeSBuZXcgc2hhZG93IHN0YWNrIGJhc2UgYWRkcmVzcyB3aXRob3V0IGNoYW5n aW5nCj4+ID4+IEFQSS4gVGhpcyBwYXRjaCBhbGxvY2F0ZXMgYSBuZXcgc2hhZG93IHN0YWNrIHdo ZW5ldmVyIENMT05FX1ZNIGlzIGdpdmVuLgo+PiA+Pgo+PiA+PiBJbiBjYXNlIG9mIENMT05FX1ZG T1JLLCBwYXJlbnQgaXMgc3VzcGVuZGVkIHVudGlsIGNoaWxkIGZpbmlzaGVzIGFuZCB0aHVzCj4+ ID4+IGNhbiBjaGlsZCB1c2UgcGFyZW50IHNoYWRvdyBzdGFjay4gSW4gY2FzZSBvZiAhQ0xPTkVf Vk0sIENPVyBraWNrcyBpbgo+PiA+PiBiZWNhdXNlIGVudGlyZSBhZGRyZXNzIHNwYWNlIGlzIGNv cGllZCBmcm9tIHBhcmVudCB0byBjaGlsZC4KPj4gPj4KPj4gPj4gYGNsb25lM2AgaXMgZXh0ZW5z aWJsZSBhbmQgY2FuIHByb3ZpZGUgbWVjaGFuaXNtcyB1c2luZyB3aGljaCBzaGFkb3cgc3RhY2sK Pj4gPj4gYXMgYW4gaW5wdXQgcGFyYW1ldGVyIGNhbiBiZSBwcm92aWRlZC4gVGhpcyBpcyBub3Qg c2V0dGxlZCB5ZXQgYW5kIGJlaW5nCj4+ID4+IGV4dGVuc2l2ZWx5IGRpc2N1c3NlZCBvbiBtYWls aW5nIGxpc3QuIE9uY2UgdGhhdCdzIHNldHRsZWQsIHRoaXMgY29tbWl0Cj4+ID4+IHdpbGwgYWRh cHQgdG8gdGhhdC4KPj4gPj4KPj4gPj4gU2lnbmVkLW9mZi1ieTogRGVlcGFrIEd1cHRhIDxkZWJ1 Z0ByaXZvc2luYy5jb20+Cj4+ID4+IC0tLQo+PiA+PiAgYXJjaC9yaXNjdi9pbmNsdWRlL2FzbS91 c2VyY2ZpLmggfCAgMjUgKysrKysrKysKPj4KPj4gLi4uIHNuaXBwZWQuLi4KPj4KPj4gPj4gKwo+ PiA+PiArLyoKPj4gPj4gKyAqIFRoaXMgZ2V0cyBjYWxsZWQgZHVyaW5nIGNsb25lL2Nsb25lMy9m b3JrLiBBbmQgaXMgbmVlZGVkIHRvIGFsbG9jYXRlIGEgc2hhZG93IHN0YWNrIGZvcgo+PiA+PiAr ICogY2FzZXMgd2hlcmUgQ0xPTkVfVk0gaXMgc3BlY2lmaWVkIGFuZCB0aHVzIGEgZGlmZmVyZW50 IHN0YWNrIGlzIHNwZWNpZmllZCBieSB1c2VyLiBXZQo+PiA+PiArICogdGh1cyBuZWVkIGEgc2Vw YXJhdGUgc2hhZG93IHN0YWNrIHRvby4gSG93IGRvZXMgc2VwYXJhdGUgc2hhZG93IHN0YWNrIGlz IHNwZWNpZmllZCBieQo+PiA+PiArICogdXNlciBpcyBzdGlsbCBiZWluZyBkZWJhdGVkLiBPbmNl IHRoYXQncyBzZXR0bGVkLCByZW1vdmUgdGhpcyBwYXJ0IG9mIHRoZSBjb21tZW50Lgo+PiA+PiAr ICogVGhpcyBmdW5jdGlvbiBzaW1wbHkgcmV0dXJucyAwIGlmIHNoYWRvdyBzdGFjayBhcmUgbm90 IHN1cHBvcnRlZCBvciBpZiBzZXBhcmF0ZSBzaGFkb3cKPj4gPj4gKyAqIHN0YWNrIGFsbG9jYXRp b24gaXMgbm90IG5lZWRlZCAobGlrZSBpbiBjYXNlIG9mICFDTE9ORV9WTSkKPj4gPj4gKyAqLwo+ PiA+PiArdW5zaWduZWQgbG9uZyBzaHN0a19hbGxvY190aHJlYWRfc3RhY2soc3RydWN0IHRhc2tf c3RydWN0ICp0c2ssCj4+ID4+ICsgICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgICAg ICAgICBjb25zdCBzdHJ1Y3Qga2VybmVsX2Nsb25lX2FyZ3MgKmFyZ3MpCj4+ID4+ICt7Cj4+ID4+ ICsgICAgICAgdW5zaWduZWQgbG9uZyBhZGRyLCBzaXplOwo+PiA+PiArCj4+ID4+ICsgICAgICAg LyogSWYgc2hhZG93IHN0YWNrIGlzIG5vdCBzdXBwb3J0ZWQsIHJldHVybiAwICovCj4+ID4+ICsg ICAgICAgaWYgKCFjcHVfc3VwcG9ydHNfc2hhZG93X3N0YWNrKCkpCj4+ID4+ICsgICAgICAgICAg ICAgICByZXR1cm4gMDsKPj4gPj4gKwo+PiA+PiArICAgICAgIC8qCj4+ID4+ICsgICAgICAgICog SWYgc2hhZG93IHN0YWNrIGlzIG5vdCBlbmFibGVkIG9uIHRoZSBuZXcgdGhyZWFkLCBza2lwIGFu eQo+PiA+PiArICAgICAgICAqIHN3aXRjaCB0byBhIG5ldyBzaGFkb3cgc3RhY2suCj4+ID4+ICsg ICAgICAgICovCj4+ID4+ICsgICAgICAgaWYgKGlzX3Noc3RrX2VuYWJsZWQodHNrKSkKPj4gPgo+ PiA+SGkgRGVlcGFrLAo+PiA+U2hvdWxkIGl0IGJlICchJyBpc19zaHN0a19lbmFibGVkKHRzayk/ Cj4+Cj4+IFllcyBpdCBpcyBhIGJ1Zy4gSXQgc2VlbXMgbGlrZSBmb3JrIHdpdGhvdXQgQ0xPTkVf Vk0gb3Igd2l0aCBDTE9ORV9WRk9SSywgaXQgd2FzIHJldHVybmluZwo+PiAwIGFueXdheXMuIEFu ZCBpbiB0aGUgY2FzZSBvZiBDTE9ORV9WTSAodXNlZCBieSBwdGhyZWFkKSwgaXQgd2FzIG5vdCBk b2luZyB0aGUgcmlnaHQgdGhpbmcuCj4KPkhpIERlZXBhaywKPkknZCBsaWtlIHRvIGtub3cgaWYg SSB1bmRlcnN0YW5kIGNvcnJlY3RseS4gQ291bGQgSSBrbm93IHdoZXRoZXIgdGhlcmUKPm1pZ2h0 IGFsc28gYmUgYSByaXNrIHdoZW4gdGhlIHVzZXIgcHJvZ3JhbSBkb2Vzbid0IGVuYWJsZSB0aGUg Q0ZJIGFuZAo+dGhlIGtlcm5lbCBkb2Vzbid0IGFjdGl2YXRlIENGSS4gQmVjYXVzZSB0aGlzIGZs b3cgd2lsbCBzdGlsbCB0cnkgdG8KPmFsbG9jYXRlIHRoZSBzaGFkb3cgc3RhY2sgYW5kIGV4ZWN1 dGUgdGhlIHNzYW1vd2FwIGNvbW1hbmQuIFRoYW5rcwoKYHNoc3RrX2FsbG9jX3RocmVhZF9zdGFj a2AgaXMgb25seSBjYWxsZWQgZnJvbSBgY29weV90aHJlYWRgIGFuZCAgYWxsb2NhdGVzIGFuZApy ZXR1cm5zIG5vbi16ZXJvIChwb3NpdGl2ZSB2YWx1ZSkgZm9yIHNzcCBvbmx5IGlmIGBDTE9ORV9W TWAgaXMgc3BlY2lmaWVkLgpgQ0xPTkVfVk1gIG1lYW5zIHRoYXQgYWRkcmVzcyBzcGFjZSBpcyBz aGFyZWQgYW5kIHVzZXJzcGFjZSBoYXMgYWxsb2NhdGVkCnNlcGFyYXRlIHN0YWNrLiBUaGlzIGZs b3cgaXMgZW5zdXJpbmcgdGhhdCBuZXdseSBjcmVhdGVkIHRocmVhZCB3aXRoIHNlcGFyYXRlCmRh dGEgc3RhY2sgZ2V0cyBhIHNlcGFyYXRlIHNoYWRvdyBzdGFjayBhcyB3ZWxsLgoKUmV0cnVuaW5n IHplcm8gdmFsdWUgZnJvbSBgc2hzdGtfYWxsb2NfdGhyZWFkX3N0YWNrYCBtZWFucyB0aGF0LCBu byBuZWVkIHRvCmFsbG9jYXRlIGEgc2hhZG93IHN0YWNrLiBJZiB5b3UgbG9vayBhdCBgY29weV90 aHJlYWRgIGZ1bmN0aW9uLCBpdCBzaW1wbHkgc2V0cwp0aGUgcmV0dXJuZWQgc3NwIGluIG5ld2x5 IGNyZWF0ZWQgdGFzaydzIHRhc2tfc3RydWN0IChpZiBpdCB3YXMgbm9uLXplcm8pLgpJZiByZXR1 cm5lZCBzc3Agd2FzIHplcm8sIGBjb3B5X3RocmVhZGAgZG9lc24ndCBkbyBhbnl0aGluZy4gVGh1 cyB3aGF0ZXZlciBpcwpjdXJyZW50IHRhc2sgc2V0dGluZ3MgYXJlIHRoYXQgd2lsbCBiZSBjb3Bp ZWQgb3ZlciB0byBuZXcgZm9ya2VkL2Nsb25lZCB0YXNrLgpJZiBjdXJyZW50IHRhc2sgaGFkIHNo YWRvdyBzdGFjayBlbmFibGVkLCBuZXcgdGFzayB3aWxsIGFsc28gZ2V0IGl0IGVuYWJsZWQgYXQK c2FtZSBhZGRyZXNzICh0byBiZSBDT1dlZCBsYXRlcikuCgpBbnkgdGFzayBnZXQgc2hhZG93IHN0 YWNrIGVuYWJsZWQgZm9yIGZpcnN0IHRpbWUgdXNpbmcgbmV3IHByY3RscyAoc2VlIHByY3RsCnBh dGNoZXMpLgoKU28gb25seSB0aW1lIGBzc2Ftb3N3YXBgIHdpbGwgYmUgZXhlcmNpc2VkIHdpbGwg YmUgYXJlCi0gVXNlciBpc3N1ZXMgZW5hYmxpbmcgYHByY3RsYCAoaXQnbGwgYmUgaXNzdWVkIGZy b20gbG9hZGVyKQotIGZvcmsvY2xvbmUgaGFwcGVucwoKSW4gYm90aCBjYXNlcywgaXQgaXMgZ3Vh cmRlZCBhZ2FpbnN0IGNoZWNrcyBvZiB3aGV0aGVyIGNwdSBzdXBwb3J0cyBpdCBhbmQgdGFzawpo YXMgc2hhZG93IHN0YWNrIGVuYWJsZWQuCgpMZXQgbWUga25vdyBpZiB5b3UgdGhpbmsgSSBtaXNz ZWQgYW55IGZsb3cuCgo+Cj4+IE1vc3Qgb2YgdGhlIHRlc3RpbmcgaGFzIGJlZW4gd2l0aCBidXN5 Ym94IGJ1aWxkIChpbmRlcGVuZGVudCBiaW5hcmllczAgZHJpdmVuIHZpYSBidWlsZHJvb3QKPj4g c2V0dXAuIFdvbmRlcmluZyB3aHkgaXQgd2Fzbid0IGNhdWdodC4KPj4KPj4gQW55d2F5cywgd2ls bCBmaXggaXQuIFRoYW5rcyBmb3IgY2F0Y2hpbmcgaXQuCj4+Cj4+ID4KPj4gPj4gKyAgICAgICAg ICAgICAgIHJldHVybiAwOwo+PiA+PiArCj4+ID4+ICsgICAgICAgLyoKCl9fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmxpbnV4LXJpc2N2IG1haWxpbmcgbGlz dApsaW51eC1yaXNjdkBsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQu b3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtcmlzY3YK