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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Xt2V72hUehROSuiTauFucVJrm/WZLwNL5WlPIaM+764nX+W7CEfpOM/qQmlI?= =?us-ascii?Q?OWHZnJuNEBz3UZcqrbQYooECIQmrb7bV7Qa7PZfJqVC3W9ZL0i1jUuP3thnh?= =?us-ascii?Q?uD2VfBIKSX3EpsFzC59mOLQnmlMV430lpKoRDP7iL3EQbMmb5gyTJp0UM0uy?= =?us-ascii?Q?Xkg7CUnTsqiJX0r3SdZoBdkG3vu6leL4RzPaswgwUXP/q8rcXf0oU3hVCyZf?= =?us-ascii?Q?al2SAZeFXylXzZw0ODwqCWxxZQuzVmB6V6cB/nQ20wM6dagZj5HacWBuYcx2?= =?us-ascii?Q?OveNHmWkp8RBvXhnlDICE7CPrxKHgNyfMc3sk328QmSDoedsCoC4O32ZDe2s?= =?us-ascii?Q?IerujZ57JBkIp1B8GSK0Vti3LuLNxtJU6kp6UHvSAK2M/tl8CqrrNVQZgmfp?= =?us-ascii?Q?1YAjz8zhOOA5BsnOMwu/AJ+PyC8UvueJEtPzhxUGBTjxQkMDT86v24LZvVTU?= =?us-ascii?Q?juAlzmuQkKZWRnSEJ46/JNIp6/gzdx2bmUOvHI/3tZdAQ1peY2fBGVJfWwzL?= =?us-ascii?Q?FO8sZVHagUZkcfiwiNvnrYmqxAcz56QxBq4+Tuo/PMppsPCBki9Cb7ErXzVG?= =?us-ascii?Q?ZOyHAgQQefwSGGWgfy5J37nwfM4E2cB4ujpEzq3D7ggMYpBydXH6Jvbw2i88?= =?us-ascii?Q?VVCTEqJENfx/NjeOch95fFAF4fISa+WjRjqugbXl3RNRsxVC7AVjETVJhkxS?= =?us-ascii?Q?2x8SiFd50Krb6d8CO39rkK8zzjoNAAL5Ln95jkXFBDPGhCNfFkQj7XUefGJa?= =?us-ascii?Q?vFU3NXXsP6xeS0vEVQqA2QTD+1FlCR7mCINVo+AyQEPu+d43zNCRHgjEovK5?= =?us-ascii?Q?Aowc/hfjlpweEzKtshH8Rvr2xdPYw64JtRQ1x4Fu0D6QFQ9jCkJ8J7amVVrp?= =?us-ascii?Q?hUdHoBSHlrbtE0p3gP4Jq20DDKBZ8GQhkAAuLUKM8HAlePtninzXGqCpBKxf?= =?us-ascii?Q?8h6uLn6SppaiZLvBYh8CmCBfam7NFrFfsze46dos+5pzoSVn/OukYS9XU2hV?= =?us-ascii?Q?DY4npCEZfl3kZQfaNJV6MVWm9npxt0M2KLwbEVFLwZrT275CRvdzYUIxso7c?= =?us-ascii?Q?WiQFPUuMFPhvg6WsvGFJw4gT9H+bVCcGOTvhpQYRxscpdCE6rGfr4tCeSIY/?= =?us-ascii?Q?u3+5y3hUD55WEeLXQumS4EqeBK2Kp/dUAxuuhoiyJhsJTuXrh7Rs9U63nscf?= =?us-ascii?Q?kS0SVur4Rt4PEjte1iDlYwa0OeEwohgKtjX8M6/Vli3tSv4nF+j3yP883nnA?= =?us-ascii?Q?8hokTLFIvBuyNIwP8gsJ6kQGoiHcMPcFhbPdsaqyms26Oijk5Eel9PjZTZ6m?= =?us-ascii?Q?YJxTDeuziERxY+oh6i4Y1nmCgU5bIdB5WefY+MYC4zc4DvBrvwZOXaveYR5Y?= =?us-ascii?Q?h6Eool6GUMqfgFgcolAqAYqdBs/9KklZPRGhygzwE7nG4uBQwzVBePJxy2Pq?= =?us-ascii?Q?YrGOs/4R4qt73bDF98M8XFoFbpW43jaCHKLAXTSqLp63gvpLrVCsyI8jy1QV?= =?us-ascii?Q?FTxH6Ojl+zjco3D2stWOacoBHUJsgVAO0WXkOM1hhepX5HZASaqLKcDfVxbA?= =?us-ascii?Q?+oRQm+EF1W9RjV02JeBBOQ5hkMuYDDwOYf73tjtwZO4V9gSfenFUP4/vgj8f?= =?us-ascii?Q?X+pnfDOAbLiX7HpDlSR2g/eqRZw23cpCP1TT2HWXHAUP8f6B8OFXcXSVZI/r?= =?us-ascii?Q?tQS7N9qpMZckmb9I6J3sMxAlQIWj/SpDGOqu4Bnane80o2+O?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5b464b43-bcc8-45dc-f76a-08de74b03fa9 X-MS-Exchange-CrossTenant-AuthSource: PA4PR04MB9366.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Feb 2026 20:55:46.6117 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: byN8Y9BjT5Fh9tbrfW6zh9hTrZ/dEuXQjOH/yPBf3KHTBvhRvkexosaXr0R+rC+gkTpkdSytvsnj4fqEV3Y2Cw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV2PR04MB11328 On Tue, Feb 24, 2026 at 10:34:53PM +0900, Koichiro Den wrote: > In pci-epf-vntb, db_count represents the total number of doorbell slots > exposed to the peer, including: > - slot #0 reserved for link events, and > - slot #1 historically unused (kept for compatibility). > > Only the remaining slots correspond to actual doorbell bits. The current > db_valid_mask() exposes all slots as valid doorbells. > > Limit db_valid_mask() to the real doorbell bits by returning > BIT_ULL(db_count - 2) - 1, and guard against db_count < 2. > > Fixes: e35f56bb0330 ("PCI: endpoint: Support NTB transfer between RC and EP") > Signed-off-by: Koichiro Den > --- Reviewed-by: Frank Li > drivers/pci/endpoint/functions/pci-epf-vntb.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c > index cbce50afc4dc..2eb3db035644 100644 > --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c > +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c > @@ -1269,7 +1269,10 @@ static int vntb_epf_peer_mw_count(struct ntb_dev *ntb) > > static u64 vntb_epf_db_valid_mask(struct ntb_dev *ntb) > { > - return BIT_ULL(ntb_ndev(ntb)->db_count) - 1; > + if (ntb_ndev(ntb)->db_count < 2) > + return 0; > + > + return BIT_ULL(ntb_ndev(ntb)->db_count - 2) - 1; > } > > static int vntb_epf_db_set_mask(struct ntb_dev *ntb, u64 db_bits) > -- > 2.51.0 >