get:
Show a patch.

patch:
Update a patch.

put:
Update a patch.

GET /api/patches/811877/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 811877,
    "url": "http://patchwork.ozlabs.org/api/patches/811877/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/linuxppc-dev/patch/1504910713-7094-22-git-send-email-linuxram@us.ibm.com/",
    "project": {
        "id": 2,
        "url": "http://patchwork.ozlabs.org/api/projects/2/?format=api",
        "name": "Linux PPC development",
        "link_name": "linuxppc-dev",
        "list_id": "linuxppc-dev.lists.ozlabs.org",
        "list_email": "linuxppc-dev@lists.ozlabs.org",
        "web_url": "https://github.com/linuxppc/wiki/wiki",
        "scm_url": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git",
        "webscm_url": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/",
        "list_archive_url": "https://lore.kernel.org/linuxppc-dev/",
        "list_archive_url_format": "https://lore.kernel.org/linuxppc-dev/{}/",
        "commit_url_format": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id={}"
    },
    "msgid": "<1504910713-7094-22-git-send-email-linuxram@us.ibm.com>",
    "list_archive_url": "https://lore.kernel.org/linuxppc-dev/1504910713-7094-22-git-send-email-linuxram@us.ibm.com/",
    "date": "2017-09-08T22:45:01",
    "name": "[13/25] powerpc: implementation for arch_override_mprotect_pkey()",
    "commit_ref": null,
    "pull_url": null,
    "state": "changes-requested",
    "archived": false,
    "hash": "5643966d07f732451f47be04ce99c80e1d319e4d",
    "submitter": {
        "id": 2667,
        "url": "http://patchwork.ozlabs.org/api/people/2667/?format=api",
        "name": "Ram Pai",
        "email": "linuxram@us.ibm.com"
    },
    "delegate": null,
    "mbox": "http://patchwork.ozlabs.org/project/linuxppc-dev/patch/1504910713-7094-22-git-send-email-linuxram@us.ibm.com/mbox/",
    "series": [
        {
            "id": 2303,
            "url": "http://patchwork.ozlabs.org/api/series/2303/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=2303",
            "date": "2017-09-08T22:44:40",
            "name": "powerpc: Free up RPAGE_RSV bits",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/2303/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/811877/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/811877/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org>",
        "X-Original-To": [
            "patchwork-incoming@ozlabs.org",
            "linuxppc-dev@lists.ozlabs.org"
        ],
        "Delivered-To": [
            "patchwork-incoming@ozlabs.org",
            "linuxppc-dev@lists.ozlabs.org"
        ],
        "Received": [
            "from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\t(using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xptlp4SPXz9sBW\n\tfor <patchwork-incoming@ozlabs.org>;\n\tSat,  9 Sep 2017 09:27:50 +1000 (AEST)",
            "from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\tby lists.ozlabs.org (Postfix) with ESMTP id 3xptlp3HN9zDrSP\n\tfor <patchwork-incoming@ozlabs.org>;\n\tSat,  9 Sep 2017 09:27:50 +1000 (AEST)",
            "from mail-qt0-x242.google.com (mail-qt0-x242.google.com\n\t[IPv6:2607:f8b0:400d:c0d::242])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128\n\tbits)) (No client certificate requested)\n\tby lists.ozlabs.org (Postfix) with ESMTPS id 3xpsrp2yZhzDrdP\n\tfor <linuxppc-dev@lists.ozlabs.org>;\n\tSat,  9 Sep 2017 08:47:06 +1000 (AEST)",
            "by mail-qt0-x242.google.com with SMTP id q8so2360196qtb.1\n\tfor <linuxppc-dev@lists.ozlabs.org>;\n\tFri, 08 Sep 2017 15:47:06 -0700 (PDT)",
            "from localhost.localdomain (50-39-103-96.bvtn.or.frontiernet.net.\n\t[50.39.103.96]) by smtp.gmail.com with ESMTPSA id\n\tx124sm2033726qka.85.2017.09.08.15.47.02\n\t(version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);\n\tFri, 08 Sep 2017 15:47:03 -0700 (PDT)"
        ],
        "Authentication-Results": [
            "ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"GC+qLuEA\"; dkim-atps=neutral",
            "lists.ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"GC+qLuEA\"; dkim-atps=neutral",
            "ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=gmail.com\n\t(client-ip=2607:f8b0:400d:c0d::242; helo=mail-qt0-x242.google.com;\n\tenvelope-from=ram.n.pai@gmail.com; receiver=<UNKNOWN>)",
            "lists.ozlabs.org; dkim=pass (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"GC+qLuEA\"; dkim-atps=neutral"
        ],
        "DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025;\n\th=sender:from:to:cc:subject:date:message-id:in-reply-to:references;\n\tbh=ffhvGSAYYl0zuVaBMwISCt8UrGJHefMpOpo06URiQnU=;\n\tb=GC+qLuEAI5yrm6uV30ktbJNQM8W4umMV9o4J0bn1RZPUXrWRz1TO4eLxYGn3vN1lUs\n\t7WZJAJnBisKbD3OIVkkef36zaxeWSVuVzLU0BcoSIQZ2eENouwmm1y4L0GcRBEN8GeKS\n\tRrtIXuiu5LyIStyPaOz8nZRd/8fq7UHd4DgzAImrkCUrNt+oa/8eDPsTjvFAR6y00Z2C\n\tC6dytHKySuoYrBfd2zQMh0vFQ1hgbMOG7IsE/YeyldY90s4/aFj+Do1mBDf2dKZwCZjz\n\tTPouzsUmRiTPW6svmztEb34Od4VXYT7G+iAqkIBSDRiO9nzoMCdUr8KBbdFvb/IWSQLr\n\tP8tw==",
        "X-Google-DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:sender:from:to:cc:subject:date:message-id\n\t:in-reply-to:references;\n\tbh=ffhvGSAYYl0zuVaBMwISCt8UrGJHefMpOpo06URiQnU=;\n\tb=lz8XFY0Ctqxoy0XRqrgu81+N9R6lS2UQ0BVsaTwdjta6LiaeMnoTDr1ZZHaA+r/2/h\n\t4l++PJ4Clr7/oZfZi8Qo+/2Xe6F68vcxNHvV7Ep3q0j4aDjvJxO8X3X+tlNqQsHmIaZS\n\tGxz5ahjX0TV9Hr0YK8s77i1JG03xW7abjY9mc+lnAkk3nwuZ0oee6UTQ9z8NH5iAtnUA\n\tarIy2uWGyV0n5hW3wXTQVA/Q/91RJylg7aHHT8v6svpN6XlyySAbODW4gSQ33HuFcE3g\n\tQBcjh9Remkf5vGqBoYv7c0Hoq0oOWs+hhG357w4c+pEERRsExwFWCYXffyLwQ34sBc5e\n\to0BA==",
        "X-Gm-Message-State": "AHPjjUh0TiFLZ9Lf48ELW6YxzCpXQX+pcqT8wGJ8Z3ZMwjoyqCplvyW/\n\td2eGXNhFTRC2ntXT",
        "X-Google-Smtp-Source": "AOwi7QC7BHQFgh9fWZApmQgMUoYjTrzw2RbBe3y7/dEUHWAhYqi0swN0DDtE5ZB/DSAnociOYussfw==",
        "X-Received": "by 10.200.28.123 with SMTP id j56mr6044793qtk.299.1504910824521; \n\tFri, 08 Sep 2017 15:47:04 -0700 (PDT)",
        "From": "Ram Pai <linuxram@us.ibm.com>",
        "To": "mpe@ellerman.id.au,\n\tlinuxppc-dev@lists.ozlabs.org",
        "Subject": "[PATCH 13/25] powerpc: implementation for\n\tarch_override_mprotect_pkey()",
        "Date": "Fri,  8 Sep 2017 15:45:01 -0700",
        "Message-Id": "<1504910713-7094-22-git-send-email-linuxram@us.ibm.com>",
        "X-Mailer": "git-send-email 1.7.1",
        "In-Reply-To": "<1504910713-7094-1-git-send-email-linuxram@us.ibm.com>",
        "References": "<1504910713-7094-1-git-send-email-linuxram@us.ibm.com>",
        "X-BeenThere": "linuxppc-dev@lists.ozlabs.org",
        "X-Mailman-Version": "2.1.23",
        "Precedence": "list",
        "List-Id": "Linux on PowerPC Developers Mail List\n\t<linuxppc-dev.lists.ozlabs.org>",
        "List-Unsubscribe": "<https://lists.ozlabs.org/options/linuxppc-dev>,\n\t<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=unsubscribe>",
        "List-Archive": "<http://lists.ozlabs.org/pipermail/linuxppc-dev/>",
        "List-Post": "<mailto:linuxppc-dev@lists.ozlabs.org>",
        "List-Help": "<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=help>",
        "List-Subscribe": "<https://lists.ozlabs.org/listinfo/linuxppc-dev>,\n\t<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=subscribe>",
        "Cc": "ebiederm@xmission.com, linuxram@us.ibm.com, mhocko@kernel.org,\n\tpaulus@samba.org, aneesh.kumar@linux.vnet.ibm.com,\n\tbauerman@linux.vnet.ibm.com, khandual@linux.vnet.ibm.com",
        "Errors-To": "linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org",
        "Sender": "\"Linuxppc-dev\"\n\t<linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org>"
    },
    "content": "arch independent code calls arch_override_mprotect_pkey()\nto return a pkey that best matches the requested protection.\n\nThis patch provides the implementation.\n\nSigned-off-by: Ram Pai <linuxram@us.ibm.com>\n---\n arch/powerpc/include/asm/mmu_context.h |    5 +++\n arch/powerpc/include/asm/pkeys.h       |   17 ++++++++++-\n arch/powerpc/mm/pkeys.c                |   47 ++++++++++++++++++++++++++++++++\n 3 files changed, 67 insertions(+), 2 deletions(-)",
    "diff": "diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h\nindex c705a5d..8e5a87e 100644\n--- a/arch/powerpc/include/asm/mmu_context.h\n+++ b/arch/powerpc/include/asm/mmu_context.h\n@@ -145,6 +145,11 @@ static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,\n #ifndef CONFIG_PPC64_MEMORY_PROTECTION_KEYS\n #define pkey_initialize()\n #define pkey_mm_init(mm)\n+\n+static inline int vma_pkey(struct vm_area_struct *vma)\n+{\n+\treturn 0;\n+}\n #endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */\n \n #endif /* __KERNEL__ */\ndiff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h\nindex f13e913..d2fffef 100644\n--- a/arch/powerpc/include/asm/pkeys.h\n+++ b/arch/powerpc/include/asm/pkeys.h\n@@ -41,6 +41,16 @@ static inline u64 pkey_to_vmflag_bits(u16 pkey)\n \t\t((pkey & 0x10UL) ? VM_PKEY_BIT4 : 0x0UL));\n }\n \n+#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | VM_PKEY_BIT1 | VM_PKEY_BIT2 | \\\n+\t\t\t\tVM_PKEY_BIT3 | VM_PKEY_BIT4)\n+\n+static inline int vma_pkey(struct vm_area_struct *vma)\n+{\n+\tif (!pkey_inited)\n+\t\treturn 0;\n+\treturn (vma->vm_flags & ARCH_VM_PKEY_FLAGS) >> VM_PKEY_SHIFT;\n+}\n+\n #define arch_max_pkey()  pkeys_total\n #define AMR_RD_BIT 0x1UL\n #define AMR_WR_BIT 0x2UL\n@@ -142,11 +152,14 @@ static inline int execute_only_pkey(struct mm_struct *mm)\n \treturn __execute_only_pkey(mm);\n }\n \n-\n+extern int __arch_override_mprotect_pkey(struct vm_area_struct *vma,\n+\t\tint prot, int pkey);\n static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma,\n \t\tint prot, int pkey)\n {\n-\treturn 0;\n+\tif (!pkey_inited)\n+\t\treturn 0;\n+\treturn __arch_override_mprotect_pkey(vma, prot, pkey);\n }\n \n extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,\ndiff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c\nindex 8a24983..fb1a76a 100644\n--- a/arch/powerpc/mm/pkeys.c\n+++ b/arch/powerpc/mm/pkeys.c\n@@ -245,3 +245,50 @@ int __execute_only_pkey(struct mm_struct *mm)\n \t\tmm->context.execute_only_pkey = execute_only_pkey;\n \treturn execute_only_pkey;\n }\n+\n+static inline bool vma_is_pkey_exec_only(struct vm_area_struct *vma)\n+{\n+\t/* Do this check first since the vm_flags should be hot */\n+\tif ((vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)) != VM_EXEC)\n+\t\treturn false;\n+\n+\treturn (vma_pkey(vma) == vma->vm_mm->context.execute_only_pkey);\n+}\n+\n+/*\n+ * This should only be called for *plain* mprotect calls.\n+ */\n+int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot,\n+\t\tint pkey)\n+{\n+\t/*\n+\t * Is this an mprotect_pkey() call?  If so, never\n+\t * override the value that came from the user.\n+\t */\n+\tif (pkey != -1)\n+\t\treturn pkey;\n+\n+\t/*\n+\t * If the currently associated pkey is execute-only,\n+\t * but the requested protection requires read or write,\n+\t * move it back to the default pkey.\n+\t */\n+\tif (vma_is_pkey_exec_only(vma) &&\n+\t    (prot & (PROT_READ|PROT_WRITE)))\n+\t\treturn 0;\n+\n+\t/*\n+\t * the requested protection is execute-only. Hence\n+\t * lets use a execute-only pkey.\n+\t */\n+\tif (prot == PROT_EXEC) {\n+\t\tpkey = execute_only_pkey(vma->vm_mm);\n+\t\tif (pkey > 0)\n+\t\t\treturn pkey;\n+\t}\n+\n+\t/*\n+\t * nothing to override.\n+\t */\n+\treturn vma_pkey(vma);\n+}\n",
    "prefixes": [
        "13/25"
    ]
}