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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CB8F0C54EBC for ; Thu, 12 Jan 2023 07:49:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236520AbjALHtL (ORCPT ); Thu, 12 Jan 2023 02:49:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36354 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239211AbjALHtC (ORCPT ); Thu, 12 Jan 2023 02:49:02 -0500 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF4C141D5C; Wed, 11 Jan 2023 23:48:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1673509736; x=1705045736; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=vMUmhc0Tn/B+KYMP/tYkNeijDWua0V32T+gVHgjqFtE=; b=Tv0DG1qvtRg0r8tFtBxqawtJqZNEKeq8JfZnZalhvI5OyrhjRFVeXCZw YUqVJDU+ioztd4gWPABdM6d5NCrfaYLQoKXqQ/7saf/RvaSqRY3fL+72F VJXKjHSKa95fISy4X6zCUHo8i1vmfae7Te09V7CQ/vB5A8LlmBh4Qjw/M pLFSkRkJNxtub+65pv130YGtm1/ETXUrBqhutcVNY/JBJscjTiLKoPBUJ o8KWVuJ2jecsE42cz9AgGWrCM1Tt03HSPAP5fpfg13MqaKkVTIdkU1kcL KzEEnZVx7sxBYe8vpRlOwoldvBb/3En7Z3SISe1cX+KwqeBs24A2HCIBo g==; X-IronPort-AV: E=Sophos;i="5.96,319,1665471600"; d="asc'?scan'208";a="131964178" Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa6.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 12 Jan 2023 00:48:54 -0700 Received: from chn-vm-ex01.mchp-main.com (10.10.85.143) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.16; Thu, 12 Jan 2023 00:48:54 -0700 Received: from wendy (10.10.115.15) by chn-vm-ex01.mchp-main.com (10.10.85.143) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.16 via Frontend Transport; Thu, 12 Jan 2023 00:48:52 -0700 Date: Thu, 12 Jan 2023 07:48:29 +0000 From: Conor Dooley To: Jisheng Zhang CC: Paul Walmsley , Palmer Dabbelt , Albert Ou , Anup Patel , Atish Patra , Heiko Stuebner , , , , , Guo Ren , Andrew Jones Subject: Re: [PATCH v3 10/13] riscv: alternative: patch alternatives in the vDSO Message-ID: References: <20230111171027.2392-1-jszhang@kernel.org> <20230111171027.2392-11-jszhang@kernel.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="6yQljiZjzbsXjRJM" Content-Disposition: inline In-Reply-To: <20230111171027.2392-11-jszhang@kernel.org> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org --6yQljiZjzbsXjRJM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hey Jisheng, On Thu, Jan 12, 2023 at 01:10:24AM +0800, Jisheng Zhang wrote: > Make it possible to use alternatives in the vDSO, so that better > implementations can be used if possible. >=20 > Signed-off-by: Jisheng Zhang > Reviewed-by: Guo Ren > Reviewed-by: Andrew Jones FYI, from this patch onwards the rv32 build is broken. Should be reproduceable with the in-tree rv32_defconfig. Unfortunately no logs for you, I've got a CI bug to fix! Thanks, Conor. > --- > arch/riscv/include/asm/vdso.h | 4 ++++ > arch/riscv/kernel/alternative.c | 25 +++++++++++++++++++++++++ > arch/riscv/kernel/vdso.c | 5 ----- > arch/riscv/kernel/vdso/vdso.lds.S | 7 +++++++ > 4 files changed, 36 insertions(+), 5 deletions(-) >=20 > diff --git a/arch/riscv/include/asm/vdso.h b/arch/riscv/include/asm/vdso.h > index a7644f46d0e5..f891478829a5 100644 > --- a/arch/riscv/include/asm/vdso.h > +++ b/arch/riscv/include/asm/vdso.h > @@ -28,8 +28,12 @@ > #define COMPAT_VDSO_SYMBOL(base, name) \ > (void __user *)((unsigned long)(base) + compat__vdso_##name##_offset) > =20 > +extern char compat_vdso_start[], compat_vdso_end[]; > + > #endif /* CONFIG_COMPAT */ > =20 > +extern char vdso_start[], vdso_end[]; > + > #endif /* !__ASSEMBLY__ */ > =20 > #endif /* CONFIG_MMU */ > diff --git a/arch/riscv/kernel/alternative.c b/arch/riscv/kernel/alternat= ive.c > index 3d4f1f32c7f6..a883a309139f 100644 > --- a/arch/riscv/kernel/alternative.c > +++ b/arch/riscv/kernel/alternative.c > @@ -11,7 +11,9 @@ > #include > #include > #include > +#include > #include > +#include > #include > #include > #include > @@ -160,6 +162,27 @@ static void __init_or_module _apply_alternatives(str= uct alt_entry *begin, > stage); > } > =20 > +static void __init apply_vdso_alternatives(void) > +{ > + const struct elf64_hdr *hdr; > + const struct elf64_shdr *shdr; > + const struct elf64_shdr *alt; > + struct alt_entry *begin, *end; > + > + hdr =3D (struct elf64_hdr *)vdso_start; > + shdr =3D (void *)hdr + hdr->e_shoff; > + alt =3D find_section(hdr, shdr, ".alternative"); > + if (!alt) > + return; > + > + begin =3D (void *)hdr + alt->sh_offset, > + end =3D (void *)hdr + alt->sh_offset + alt->sh_size, > + > + _apply_alternatives((struct alt_entry *)begin, > + (struct alt_entry *)end, > + RISCV_ALTERNATIVES_BOOT); > +} > + > void __init apply_boot_alternatives(void) > { > /* If called on non-boot cpu things could go wrong */ > @@ -168,6 +191,8 @@ void __init apply_boot_alternatives(void) > _apply_alternatives((struct alt_entry *)__alt_start, > (struct alt_entry *)__alt_end, > RISCV_ALTERNATIVES_BOOT); > + > + apply_vdso_alternatives(); > } > =20 > /* > diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c > index e410275918ac..4e631c098f4d 100644 > --- a/arch/riscv/kernel/vdso.c > +++ b/arch/riscv/kernel/vdso.c > @@ -22,11 +22,6 @@ struct vdso_data { > }; > #endif > =20 > -extern char vdso_start[], vdso_end[]; > -#ifdef CONFIG_COMPAT > -extern char compat_vdso_start[], compat_vdso_end[]; > -#endif > - > enum vvar_pages { > VVAR_DATA_PAGE_OFFSET, > VVAR_TIMENS_PAGE_OFFSET, > diff --git a/arch/riscv/kernel/vdso/vdso.lds.S b/arch/riscv/kernel/vdso/v= dso.lds.S > index 150b1a572e61..4a0606633290 100644 > --- a/arch/riscv/kernel/vdso/vdso.lds.S > +++ b/arch/riscv/kernel/vdso/vdso.lds.S > @@ -40,6 +40,13 @@ SECTIONS > . =3D 0x800; > .text : { *(.text .text.*) } :text > =20 > + . =3D ALIGN(4); > + .alternative : { > + __alt_start =3D .; > + *(.alternative) > + __alt_end =3D .; > + } > + > .data : { > *(.got.plt) *(.got) > *(.data .data.* .gnu.linkonce.d.*) > --=20 > 2.38.1 >=20 --6yQljiZjzbsXjRJM Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCY7+7PwAKCRB4tDGHoIJi 0uEeAQD9G+uLbu+8Gxiocxeb/U5F/Z622cqxCP2S5hcdl9HrxAEA5R0sXrC2ZRY9 VB1eNSPNCHca9c/1ktnoYwr7MSa5TQc= =LDuC -----END PGP SIGNATURE----- --6yQljiZjzbsXjRJM--