From 0b261d7c1cd32dc93cbc92425fb55e67b24c6638 Mon Sep 17 00:00:00 2001 From: Leon Romanovsky Date: Thu, 22 May 2025 14:36:18 +0300 Subject: [PATCH] RDMA/rxe: Break endless pagefault loop for RO pages RO pages has "perm" equal to 0, that caused to the situation where such pages were marked as needed to have fault and caused to infinite loop. Fixes: eedd5b1276e7 ("RDMA/umem: Store ODP access mask information in PFN") Reported-by: Daisuke Matsuda Closes: https://lore.kernel.org/all/3016329a-4edd-4550-862f-b298a1b79a39@gmail.com/ Link: https://patch.msgid.link/096fab178d48ed86942ee22eafe9be98e29092aa.1747913377.git.leonro@nvidia.com Tested-by: Daisuke Matsuda Signed-off-by: Leon Romanovsky --- drivers/infiniband/sw/rxe/rxe_odp.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/drivers/infiniband/sw/rxe/rxe_odp.c b/drivers/infiniband/sw/rxe/rxe_odp.c index a1416626f61a5..dbc5a5600eb78 100644 --- a/drivers/infiniband/sw/rxe/rxe_odp.c +++ b/drivers/infiniband/sw/rxe/rxe_odp.c @@ -124,8 +124,8 @@ int rxe_odp_mr_init_user(struct rxe_dev *rxe, u64 start, u64 length, return err; } -static inline bool rxe_check_pagefault(struct ib_umem_odp *umem_odp, - u64 iova, int length, u32 perm) +static inline bool rxe_check_pagefault(struct ib_umem_odp *umem_odp, u64 iova, + int length) { bool need_fault = false; u64 addr; @@ -137,7 +137,7 @@ static inline bool rxe_check_pagefault(struct ib_umem_odp *umem_odp, while (addr < iova + length) { idx = (addr - ib_umem_start(umem_odp)) >> umem_odp->page_shift; - if (!(umem_odp->map.pfn_list[idx] & perm)) { + if (!(umem_odp->map.pfn_list[idx] & HMM_PFN_VALID)) { need_fault = true; break; } @@ -161,18 +161,14 @@ static int rxe_odp_map_range_and_lock(struct rxe_mr *mr, u64 iova, int length, u { struct ib_umem_odp *umem_odp = to_ib_umem_odp(mr->umem); bool need_fault; - u64 perm = 0; int err; if (unlikely(length < 1)) return -EINVAL; - if (!(flags & RXE_PAGEFAULT_RDONLY)) - perm |= HMM_PFN_WRITE; - mutex_lock(&umem_odp->umem_mutex); - need_fault = rxe_check_pagefault(umem_odp, iova, length, perm); + need_fault = rxe_check_pagefault(umem_odp, iova, length); if (need_fault) { mutex_unlock(&umem_odp->umem_mutex); @@ -182,7 +178,7 @@ static int rxe_odp_map_range_and_lock(struct rxe_mr *mr, u64 iova, int length, u if (err < 0) return err; - need_fault = rxe_check_pagefault(umem_odp, iova, length, perm); + need_fault = rxe_check_pagefault(umem_odp, iova, length); if (need_fault) return -EFAULT; } -- 2.47.3