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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 25864C433F5 for ; Wed, 23 Feb 2022 11:50:40 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4K3Z9V0pX4z3cDC for ; Wed, 23 Feb 2022 22:50:38 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=EOJnR4gJ; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=145.40.68.75; helo=ams.source.kernel.org; envelope-from=guoren@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=EOJnR4gJ; dkim-atps=neutral Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4K3Z8n5WSrz2xB1 for ; Wed, 23 Feb 2022 22:50:01 +1100 (AEDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 7A7A1B81DD8 for ; Wed, 23 Feb 2022 11:49:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3C84AC340EB for ; Wed, 23 Feb 2022 11:49:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645616996; bh=hfHAFROwfpOFFi/tQhhl9G3FjcazCR7QoA9DMgKIuUs=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=EOJnR4gJ7ufXtY/T43KGngmiB+iKTj+5cW86rQLuY+AjanWMIJyMBhBaRqmwDJD4N V/9ez038ffWbHbyJH72BzMeOVgAiIxHgggY4rvgT6/A5uwAL3ZDFJx0ocryfEaL67z 1dihWRgm5e/JWnIzCiAyxJME5lsoD/4hfcIYkmp9JBQ6ltc+Hx+U9A5YZod1iPgQtV C9zDSuh4UoJNuPnSWSxAntKHNDYOL5EwEZJ4Qr4VhtTjs9Elsutn1KsWJTVGiwCo4+ xA4TmD5EiA26macIZsqIXj2wnzfpGEUoGtufgWDeRcYGNP5WYhYqUNCuKd7osCCi2C fXrTfME84AP9w== Received: by mail-vk1-f172.google.com with SMTP id k9so5470300vki.4 for ; Wed, 23 Feb 2022 03:49:56 -0800 (PST) X-Gm-Message-State: AOAM531c5k6zZIigdTKCbmWD1wqB9RnAliAaHhu0I7MZ2Y3r4ytJUxtQ srjQ2k7KqRMbESsnEUebzqxbFvdvNcDlqLptRdU= X-Google-Smtp-Source: ABdhPJyqJLnPeoxGeO22JI8w60FhVdlZOJm/ivkvGivlInjfGWyPsT7PT1FafotgeKHBNd2cGszxDxqC/GZp/VCntVY= X-Received: by 2002:a05:6122:887:b0:332:699e:7e67 with SMTP id 7-20020a056122088700b00332699e7e67mr1087720vkf.35.1645616995136; Wed, 23 Feb 2022 03:49:55 -0800 (PST) MIME-Version: 1.0 References: <20220201150545.1512822-18-guoren@kernel.org> In-Reply-To: From: Guo Ren Date: Wed, 23 Feb 2022 19:49:44 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH V5 17/21] riscv: compat: vdso: Add setup additional pages implementation To: Palmer Dabbelt Content-Type: text/plain; charset="UTF-8" X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch , linux-s390 , Guo Ren , Parisc List , Arnd Bergmann , Greg KH , Drew Fustini , Anup Patel , Wang Junqiang , the arch/x86 maintainers , Linux Kernel Mailing List , linux-csky@vger.kernel.org, "open list:BROADCOM NVRAM DRIVER" , liush , sparclinux , linux-riscv , linuxppc-dev , Christoph Hellwig , Linux ARM , Wei Fu Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, Feb 23, 2022 at 9:42 AM Palmer Dabbelt wrote: > > On Tue, 01 Feb 2022 07:05:41 PST (-0800), guoren@kernel.org wrote: > > From: Guo Ren > > > > Reconstruct __setup_additional_pages() by appending vdso info > > pointer argument to meet compat_vdso_info requirement. And change > > vm_special_mapping *dm, *cm initialization into static. > > > > Signed-off-by: Guo Ren > > Signed-off-by: Guo Ren > > Cc: Arnd Bergmann > > Cc: Palmer Dabbelt > > --- > > arch/riscv/include/asm/elf.h | 5 ++ > > arch/riscv/include/asm/mmu.h | 1 + > > arch/riscv/kernel/vdso.c | 104 +++++++++++++++++++++++++---------- > > 3 files changed, 81 insertions(+), 29 deletions(-) > > > > diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h > > index 3a4293dc7229..d87d3bcc758d 100644 > > --- a/arch/riscv/include/asm/elf.h > > +++ b/arch/riscv/include/asm/elf.h > > @@ -134,5 +134,10 @@ do { if ((ex).e_ident[EI_CLASS] == ELFCLASS32) \ > > typedef compat_ulong_t compat_elf_greg_t; > > typedef compat_elf_greg_t compat_elf_gregset_t[ELF_NGREG]; > > > > +extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm, > > + int uses_interp); > > +#define compat_arch_setup_additional_pages \ > > + compat_arch_setup_additional_pages > > + > > #endif /* CONFIG_COMPAT */ > > #endif /* _ASM_RISCV_ELF_H */ > > diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h > > index 0099dc116168..cedcf8ea3c76 100644 > > --- a/arch/riscv/include/asm/mmu.h > > +++ b/arch/riscv/include/asm/mmu.h > > @@ -16,6 +16,7 @@ typedef struct { > > atomic_long_t id; > > #endif > > void *vdso; > > + void *vdso_info; > > #ifdef CONFIG_SMP > > /* A local icache flush is needed before user execution can resume. */ > > cpumask_t icache_stale_mask; > > diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c > > index a9436a65161a..deca69524799 100644 > > --- a/arch/riscv/kernel/vdso.c > > +++ b/arch/riscv/kernel/vdso.c > > @@ -23,6 +23,9 @@ struct vdso_data { > > #endif > > > > 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, > > @@ -30,6 +33,11 @@ enum vvar_pages { > > VVAR_NR_PAGES, > > }; > > > > +enum rv_vdso_map { > > + RV_VDSO_MAP_VVAR, > > + RV_VDSO_MAP_VDSO, > > +}; > > + > > #define VVAR_SIZE (VVAR_NR_PAGES << PAGE_SHIFT) > > > > /* > > @@ -52,12 +60,6 @@ struct __vdso_info { > > struct vm_special_mapping *cm; > > }; > > > > -static struct __vdso_info vdso_info __ro_after_init = { > > - .name = "vdso", > > - .vdso_code_start = vdso_start, > > - .vdso_code_end = vdso_end, > > -}; > > - > > static int vdso_mremap(const struct vm_special_mapping *sm, > > struct vm_area_struct *new_vma) > > { > > @@ -66,35 +68,35 @@ static int vdso_mremap(const struct vm_special_mapping *sm, > > return 0; > > } > > > > -static int __init __vdso_init(void) > > +static int __init __vdso_init(struct __vdso_info *vdso_info) > > { > > unsigned int i; > > struct page **vdso_pagelist; > > unsigned long pfn; > > > > - if (memcmp(vdso_info.vdso_code_start, "\177ELF", 4)) { > > + if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4)) { > > pr_err("vDSO is not a valid ELF object!\n"); > > return -EINVAL; > > } > > > > - vdso_info.vdso_pages = ( > > - vdso_info.vdso_code_end - > > - vdso_info.vdso_code_start) >> > > + vdso_info->vdso_pages = ( > > + vdso_info->vdso_code_end - > > + vdso_info->vdso_code_start) >> > > PAGE_SHIFT; > > > > - vdso_pagelist = kcalloc(vdso_info.vdso_pages, > > + vdso_pagelist = kcalloc(vdso_info->vdso_pages, > > sizeof(struct page *), > > GFP_KERNEL); > > if (vdso_pagelist == NULL) > > return -ENOMEM; > > > > /* Grab the vDSO code pages. */ > > - pfn = sym_to_pfn(vdso_info.vdso_code_start); > > + pfn = sym_to_pfn(vdso_info->vdso_code_start); > > > > - for (i = 0; i < vdso_info.vdso_pages; i++) > > + for (i = 0; i < vdso_info->vdso_pages; i++) > > vdso_pagelist[i] = pfn_to_page(pfn + i); > > > > - vdso_info.cm->pages = vdso_pagelist; > > + vdso_info->cm->pages = vdso_pagelist; > > > > return 0; > > } > > @@ -116,13 +118,14 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns) > > { > > struct mm_struct *mm = task->mm; > > struct vm_area_struct *vma; > > + struct __vdso_info *vdso_info = mm->context.vdso_info; > > IIUC this is the only use for context.vdso_info? If that's the case, > can we just switch between VDSO targets based on __is_compat_task(task)? > That'd save an mm_struct pointer, which is always nice. It'd probably > be worth cleaning up the arm64 port too, which zaps both mappings. > > > > > mmap_read_lock(mm); > > > > for (vma = mm->mmap; vma; vma = vma->vm_next) { > > unsigned long size = vma->vm_end - vma->vm_start; > > > > - if (vma_is_special_mapping(vma, vdso_info.dm)) > > + if (vma_is_special_mapping(vma, vdso_info->dm)) > > zap_page_range(vma, vma->vm_start, size); > > } > > > > @@ -187,11 +190,6 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, > > return vmf_insert_pfn(vma, vmf->address, pfn); > > } > > > > -enum rv_vdso_map { > > - RV_VDSO_MAP_VVAR, > > - RV_VDSO_MAP_VDSO, > > -}; > > - > > static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = { > > [RV_VDSO_MAP_VVAR] = { > > .name = "[vvar]", > > @@ -203,25 +201,53 @@ static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = { > > }, > > }; > > > > +static struct __vdso_info vdso_info __ro_after_init = { > > + .name = "vdso", > > + .vdso_code_start = vdso_start, > > + .vdso_code_end = vdso_end, > > + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR], > > + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO], > > +}; > > + > > +#ifdef CONFIG_COMPAT > > +static struct __vdso_info compat_vdso_info __ro_after_init = { > > + .name = "compat_vdso", > > + .vdso_code_start = compat_vdso_start, > > + .vdso_code_end = compat_vdso_end, > > + .dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR], > > + .cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO], > > +}; > > +#endif > > + > > static int __init vdso_init(void) > > { > > - vdso_info.dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR]; > > - vdso_info.cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO]; > > + int ret; > > + > > + ret = __vdso_init(&vdso_info); > > + if (ret) > > + goto out; > > > > - return __vdso_init(); > > +#ifdef CONFIG_COMPAT > > + ret = __vdso_init(&compat_vdso_info); > > + if (ret) > > + goto out; > > It's a bit pedantic (we're just going to crash anyway), but this is > mising the cleanup for the first __vdso_init(). I would use panic in __vdso_init: static void __init __vdso_init(struct __vdso_info *vdso_info) { ... if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4)) { - pr_err("vDSO is not a valid ELF object!\n"); - return -EINVAL; + panic("vDSO is not a valid ELF object!\n"); } > > > +#endif > > +out: > > + return ret; > > } > > arch_initcall(vdso_init); > > > > static int __setup_additional_pages(struct mm_struct *mm, > > struct linux_binprm *bprm, > > - int uses_interp) > > + int uses_interp, > > + struct __vdso_info *vdso_info) > > { > > unsigned long vdso_base, vdso_text_len, vdso_mapping_len; > > void *ret; > > > > BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES); > > > > - vdso_text_len = vdso_info.vdso_pages << PAGE_SHIFT; > > + vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT; > > /* Be sure to map the data page */ > > vdso_mapping_len = vdso_text_len + VVAR_SIZE; > > > > @@ -232,16 +258,18 @@ static int __setup_additional_pages(struct mm_struct *mm, > > } > > > > ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE, > > - (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info.dm); > > + (VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info->dm); > > if (IS_ERR(ret)) > > goto up_fail; > > > > vdso_base += VVAR_SIZE; > > mm->context.vdso = (void *)vdso_base; > > + mm->context.vdso_info = (void *)vdso_info; > > + > > ret = > > _install_special_mapping(mm, vdso_base, vdso_text_len, > > (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC), > > - vdso_info.cm); > > + vdso_info->cm); > > > > if (IS_ERR(ret)) > > goto up_fail; > > @@ -253,6 +281,24 @@ static int __setup_additional_pages(struct mm_struct *mm, > > return PTR_ERR(ret); > > } > > > > +#ifdef CONFIG_COMPAT > > +int compat_arch_setup_additional_pages(struct linux_binprm *bprm, > > + int uses_interp) > > +{ > > + struct mm_struct *mm = current->mm; > > + int ret; > > + > > + if (mmap_write_lock_killable(mm)) > > + return -EINTR; > > + > > + ret = __setup_additional_pages(mm, bprm, uses_interp, > > + &compat_vdso_info); > > + mmap_write_unlock(mm); > > + > > + return ret; > > +} > > +#endif > > + > > int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) > > { > > struct mm_struct *mm = current->mm; > > @@ -261,7 +307,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) > > if (mmap_write_lock_killable(mm)) > > return -EINTR; > > > > - ret = __setup_additional_pages(mm, bprm, uses_interp); > > + ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info); > > mmap_write_unlock(mm); > > > > return ret; > > Reviewed-by: Palmer Dabbelt > > As I don't think either of these are big enough of a deal to keep from merging > this. -- Best Regards Guo Ren ML: https://lore.kernel.org/linux-csky/