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X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?50qgKQ8DTPsQFsKLA26FnAKFtDrYIP1O9mTPBn4FQkVwEx2Jq6lGznTgFACZ?= =?us-ascii?Q?9LWJnzro5cSNsJZOxnbOT4KMSs4cKN+Hm1hbCd60ZchDepbsJi5BGmT3qdPq?= =?us-ascii?Q?qLttT/EcLnlV/ClPX7VSyu3x7nkcUTl39ZiP0FF/wfIxbYO6cojw+ewqhDHA?= =?us-ascii?Q?15+1GG9tzW1HrS13FIYXKLvDjkA8KqEcTEpokM/pcow7TSNsRjdA2Qu9pm1H?= =?us-ascii?Q?LDDwRiPw/4nG0HQp4mwiq/HDa1JtjIzM9sP4LehDFgo/m05nEk7v6wLXePgW?= =?us-ascii?Q?F2yETLRKMTQkP7CnR4GDO0YaZ0D4JwMfSDSq8G9DxOOP+2aZNoHuta1rkwQj?= =?us-ascii?Q?lc/OewWAm4hCpklgGmEWV0aPWy14MtpX84PhjBK62V5opZULLP72RLS89IPh?= =?us-ascii?Q?7xhZ9677xYBInTz0lQisGhnzSg3Lw6vnhcna9aohjGVNtRw+HaGGs5KgNXhY?= =?us-ascii?Q?q5lgo8PK7DwoplYjeTZbUVpGoSy2W6xjTcPuaP9Fb8pjJgnoOr5RB9Rcujz0?= =?us-ascii?Q?QCPf03FgQvg1Mh9/tqLE3E2Fzm9QXVb9l/P9C9IdQu/ESmrvX6RxxnFMWx90?= =?us-ascii?Q?+dgHg3mYawT18/n8x4Tl2/8ZxTmGQap8mBfNH4DOt4L6jB99/L7i0kjlhEXM?= =?us-ascii?Q?Y/tkePynF5qitjFbVP02/ny7RoA3BU/lBBVPq4b4TPuW5fL4mRdNyUrT+LoA?= =?us-ascii?Q?v5I9lv6RRI1mj0fRSluYb/yfCTFudzeCAkDnOtgBA/dhfUAbFjfsKWFK2VjG?= =?us-ascii?Q?kuSvYrEAMQgl0hDmTZJmpMDZ9tCTf5RwQiS8513gwYForBX6+Hm61COad281?= =?us-ascii?Q?4PmYN/r9wpiqF3Tyh1PwuPMI/wmnQ5x+AUBdmSGvURh+ZXCuGFffXvl4QYrJ?= =?us-ascii?Q?MpKEUCbkPd/+Jq8Q6gXwvGeE/kX2gMfdIWzKWNRHnZTQBNHDcAKXzSVNpKtc?= =?us-ascii?Q?gUpU605Y9pNbWUxtsBzRSrYdfjIws9x6JFaRZBI9zLDEDUvHObJrWmoLcgW0?= =?us-ascii?Q?JEZ7m2g2tVHjOtsc4sPAcmcMjXSJmbx2YI3HQ9wnx1BwYjpRpei2/pR4Utvw?= =?us-ascii?Q?cdnOER875xyucCaOL6bIQ81ZHbMyt+iqOYoEnE/2MdbizZPjIU4qXcqn7Ntq?= =?us-ascii?Q?BXDvFTcRLBPXYs9prYUvayKK9ZsHRgRYU/T2nGq9d3Y6gK4nuiHnKajPZIO/?= =?us-ascii?Q?ZWdW+2k0qvFc4eKbDE0f6MvhebEdfcuMXEgCNbYlMv+/95fsNaMo5s2PtXOh?= =?us-ascii?Q?JMKdOfFmna6ZLmbR8lV8y0r6Ld2Njxag+736ZqTSB56l7M/aTz0nBsh5UVgl?= =?us-ascii?Q?j+5mkE/U9No9toLCrMb08N23?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4ebc22bb-a8ca-40e8-4160-08d922175d08 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 May 2021 20:29:59.1185 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: LhcF/7cjtvZg3NV2JqfwYKXfkDk3vEgZQsBvZbeQFQHrG9uYzd6bjufZXWN3W87c X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5269 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Thu, May 27, 2021 at 02:47:45PM -0500, Bob Pearson wrote: > These patches optimize the memory ordering in rxe_queue.h so > that user space and not kernel space indices are protected for loads > with smp_load_acquire() and stores with smp_store_release(). The > original implementation of this did not apply to all index references > which has recently caused test case errors traced to stale memory loads. > These patches fix those errors and also protect kernel indices from > malicious modification by user space. I didn't read it carefully, but I think this captures the basic solution Jason