From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3B6781494CC for ; Mon, 21 Apr 2025 02:09:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745201371; cv=none; b=N0cOINLsgxF6g2biNGj5BHB0Jc6IKADFINXxE5z2/zxuDHaVRNh1lcqye0mXFtHN+/QH9JfX1VgGOjZcekQ3swZVXCg0ycsaEMJ612wWEHfsDCiyZ/Xf0/IkKTjC0ENS4Cm0Bzn7FZ1TXR4D+JKylt+CRLoJ6ODxBCrxPNiGDJ8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745201371; c=relaxed/simple; bh=8665lUcagk6SBaoe799Wqq8bT+Js0KNMGAIWgtHXrB8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=oqJIOZGRVdi07UAVzM84zy3pLuuuVPAdDBk/QOM+jF/5OeZkrcg1NM2de7Iz6CmC5CZiTgqDJ79Qpjx+hUuHCHliQgc6oF8KXrqJ/SSOVJj9IrwNQTxfK03VT5Y0XT6N0Z20GSN6gSumZ+exrspohBfRJujLGE/CB0RAtYzItH0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Q/uveT18; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Q/uveT18" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1745201367; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=656yZBycWTbOcI/QDkiraTK+o6zkkKhUlNx/4jNdMZQ=; b=Q/uveT18ob0kT/xdNkWH4eSfrARBjiIncIQvZ75y7URBlFC2AI3J6wb5BkA4VDegU42UOT vIcQToBMkcbb4ygjpT/UsWH6WjoVTSwjUTl6hn7HchS5haoYemCdSyIgH7myVcMQxWoJT4 47NP3e9goICVA9SSoTLosWDvviO60kA= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-627-pYxh_6rgOYKb0DbUIMnJ8w-1; Sun, 20 Apr 2025 22:09:22 -0400 X-MC-Unique: pYxh_6rgOYKb0DbUIMnJ8w-1 X-Mimecast-MFC-AGG-ID: pYxh_6rgOYKb0DbUIMnJ8w_1745201360 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 373B31800446; Mon, 21 Apr 2025 02:09:20 +0000 (UTC) Received: from localhost (unknown [10.72.112.5]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C4A2B19560A3; Mon, 21 Apr 2025 02:09:16 +0000 (UTC) Date: Mon, 21 Apr 2025 10:09:12 +0800 From: Baoquan He To: steven chen Cc: zohar@linux.ibm.com, stefanb@linux.ibm.com, roberto.sassu@huaweicloud.com, roberto.sassu@huawei.com, eric.snowberg@oracle.com, ebiederm@xmission.com, paul@paul-moore.com, code@tyhicks.com, bauermann@kolabnow.com, linux-integrity@vger.kernel.org, kexec@lists.infradead.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, madvenka@linux.microsoft.com, nramas@linux.microsoft.com, James.Bottomley@hansenpartnership.com, vgoyal@redhat.com, dyoung@redhat.com Subject: Re: [PATCH v12 3/9] kexec: define functions to map and unmap segments Message-ID: References: <20250416021028.1403-1-chenste@linux.microsoft.com> <20250416021028.1403-4-chenste@linux.microsoft.com> <95d249ef-bfb3-431f-b633-8b3de383e067@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <95d249ef-bfb3-431f-b633-8b3de383e067@linux.microsoft.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 On 04/20/25 at 05:30am, steven chen wrote: > On 4/17/2025 9:36 PM, Baoquan He wrote: > > On 04/15/25 at 07:10pm, steven chen wrote: > > > From: Steven Chen > > ^^^^^^ > > > Implement kimage_map_segment() to enable IMA to map the measurement log > > > list to the kimage structure during the kexec 'load' stage. This function > > > gathers the source pages within the specified address range, and maps them > > > to a contiguous virtual address range. > > > > > > This is a preparation for later usage. > > > > > > Implement kimage_unmap_segment() for unmapping segments using vunmap(). > > > > > > From: Tushar Sugandhi > > ^^^^^^ > > > Signed-off-by: Tushar Sugandhi > > ^^^^^^^ > > > Cc: Eric Biederman > > > Cc: Baoquan He > > > Cc: Vivek Goyal > > > Cc: Dave Young > > > Signed-off-by: steven chen > > ^^^^^ > > > > The signing on this patch is a little confusing. I can't see who is the > > real author, who is the co-author, between you and Tushar. You may need > > to refer to Documentation/process/5.Posting.rst to make that clear. > > Hi Baoquan, > > From my understanding, if there is no change from the original author patch, > need to add > From tag and Signed-off-by tag; otherwise, if there are changes, > Signed-off-by can be used. If you don't change a patch, you can add your Signed-off-by when posting. However, the From decides who is the real author. There's no way to have two From on one patch. My personal understanding. > > Steven > > > > Acked-by: Baoquan He > > > --- > > > include/linux/kexec.h | 6 +++++ > > > kernel/kexec_core.c | 54 +++++++++++++++++++++++++++++++++++++++++++ > > > 2 files changed, 60 insertions(+) > > > > > > diff --git a/include/linux/kexec.h b/include/linux/kexec.h > > > index f0e9f8eda7a3..7d6b12f8b8d0 100644 > > > --- a/include/linux/kexec.h > > > +++ b/include/linux/kexec.h > > > @@ -467,13 +467,19 @@ extern bool kexec_file_dbg_print; > > > #define kexec_dprintk(fmt, arg...) \ > > > do { if (kexec_file_dbg_print) pr_info(fmt, ##arg); } while (0) > > > +extern void *kimage_map_segment(struct kimage *image, unsigned long addr, unsigned long size); > > > +extern void kimage_unmap_segment(void *buffer); > > > #else /* !CONFIG_KEXEC_CORE */ > > > struct pt_regs; > > > struct task_struct; > > > +struct kimage; > > > static inline void __crash_kexec(struct pt_regs *regs) { } > > > static inline void crash_kexec(struct pt_regs *regs) { } > > > static inline int kexec_should_crash(struct task_struct *p) { return 0; } > > > static inline int kexec_crash_loaded(void) { return 0; } > > > +static inline void *kimage_map_segment(struct kimage *image, unsigned long addr, unsigned long size) > > > +{ return NULL; } > > > +static inline void kimage_unmap_segment(void *buffer) { } > > > #define kexec_in_progress false > > > #endif /* CONFIG_KEXEC_CORE */ > > > diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c > > > index c0bdc1686154..a5e378e1dc7f 100644 > > > --- a/kernel/kexec_core.c > > > +++ b/kernel/kexec_core.c > > > @@ -867,6 +867,60 @@ int kimage_load_segment(struct kimage *image, > > > return result; > > > } > > > +void *kimage_map_segment(struct kimage *image, > > > + unsigned long addr, unsigned long size) > > > +{ > > > + unsigned long src_page_addr, dest_page_addr = 0; > > > + unsigned long eaddr = addr + size; > > > + kimage_entry_t *ptr, entry; > > > + struct page **src_pages; > > > + unsigned int npages; > > > + void *vaddr = NULL; > > > + int i; > > > + > > > + /* > > > + * Collect the source pages and map them in a contiguous VA range. > > > + */ > > > + npages = PFN_UP(eaddr) - PFN_DOWN(addr); > > > + src_pages = kmalloc_array(npages, sizeof(*src_pages), GFP_KERNEL); > > > + if (!src_pages) { > > > + pr_err("Could not allocate ima pages array.\n"); > > > + return NULL; > > > + } > > > + > > > + i = 0; > > > + for_each_kimage_entry(image, ptr, entry) { > > > + if (entry & IND_DESTINATION) { > > > + dest_page_addr = entry & PAGE_MASK; > > > + } else if (entry & IND_SOURCE) { > > > + if (dest_page_addr >= addr && dest_page_addr < eaddr) { > > > + src_page_addr = entry & PAGE_MASK; > > > + src_pages[i++] = > > > + virt_to_page(__va(src_page_addr)); > > > + if (i == npages) > > > + break; > > > + dest_page_addr += PAGE_SIZE; > > > + } > > > + } > > > + } > > > + > > > + /* Sanity check. */ > > > + WARN_ON(i < npages); > > > + > > > + vaddr = vmap(src_pages, npages, VM_MAP, PAGE_KERNEL); > > > + kfree(src_pages); > > > + > > > + if (!vaddr) > > > + pr_err("Could not map ima buffer.\n"); > > > + > > > + return vaddr; > > > +} > > > + > > > +void kimage_unmap_segment(void *segment_buffer) > > > +{ > > > + vunmap(segment_buffer); > > > +} > > > + > > > struct kexec_load_limit { > > > /* Mutex protects the limit count. */ > > > struct mutex mutex; > > > -- > > > 2.43.0 > > > >