[leon-rdma:rdma-next 43/50] drivers/infiniband/hw/mlx5/odp.c:572:3: warning: variable 'access_mask' is uninitialized when used here

[leon-rdma:rdma-next 43/50] drivers/infiniband/hw/mlx5/odp.c:572:3: warning: variable 'access_mask' is uninitialized when used here

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/leon/linux-rdma.git rdma-next
head:   17282587cdc0f20c27d7404ac1caa5ebe4e9d87b
commit: 0f8d73f33588b9e1db56ab89f2eb7d1cb7f30583 [43/50] RDMA/umem: Store ODP access mask information in PFN
config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20240201/202402010925.gklK6eFn-lkp@intel.com/config)
compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project fdac7d0b6f74f919d319b31a0680c77f66732586)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240201/202402010925.gklK6eFn-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202402010925.gklK6eFn-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/infiniband/hw/mlx5/odp.c:572:3: warning: variable 'access_mask' is uninitialized when used here [-Wuninitialized]
     572 |                 access_mask |= HMM_PFN_WRITE;
         |                 ^~~~~~~~~~~
   drivers/infiniband/hw/mlx5/odp.c:557:17: note: initialize the variable 'access_mask' to silence this warning
     557 |         u64 access_mask;
         |                        ^
         |                         = 0
   1 warning generated.


vim +/access_mask +572 drivers/infiniband/hw/mlx5/odp.c

   547	
   548	#define MLX5_PF_FLAGS_DOWNGRADE BIT(1)
   549	#define MLX5_PF_FLAGS_SNAPSHOT BIT(2)
   550	#define MLX5_PF_FLAGS_ENABLE BIT(3)
   551	static int pagefault_real_mr(struct mlx5_ib_mr *mr, struct ib_umem_odp *odp,
   552				     u64 user_va, size_t bcnt, u32 *bytes_mapped,
   553				     u32 flags)
   554	{
   555		int page_shift, ret, np;
   556		bool downgrade = flags & MLX5_PF_FLAGS_DOWNGRADE;
   557		u64 access_mask;
   558		u64 start_idx;
   559		bool fault = !(flags & MLX5_PF_FLAGS_SNAPSHOT);
   560		u32 xlt_flags = MLX5_IB_UPD_XLT_ATOMIC;
   561	
   562		if (flags & MLX5_PF_FLAGS_ENABLE)
   563			xlt_flags |= MLX5_IB_UPD_XLT_ENABLE;
   564	
   565		if (flags & MLX5_PF_FLAGS_DOWNGRADE)
   566			xlt_flags |= MLX5_IB_UPD_XLT_DOWNGRADE;
   567	
   568		page_shift = odp->page_shift;
   569		start_idx = (user_va - ib_umem_start(odp)) >> page_shift;
   570	
   571		if (odp->umem.writable && !downgrade)
 > 572			access_mask |= HMM_PFN_WRITE;
   573	
   574		np = ib_umem_odp_map_dma_and_lock(odp, user_va, bcnt, access_mask, fault);
   575		if (np < 0)
   576			return np;
   577	
   578		/*
   579		 * No need to check whether the MTTs really belong to this MR, since
   580		 * ib_umem_odp_map_dma_and_lock already checks this.
   581		 */
   582		ret = mlx5r_umr_update_xlt(mr, start_idx, np, page_shift, xlt_flags);
   583		mutex_unlock(&odp->umem_mutex);
   584	
   585		if (ret < 0) {
   586			if (ret != -EAGAIN)
   587				mlx5_ib_err(mr_to_mdev(mr),
   588					    "Failed to update mkey page tables\n");
   589			goto out;
   590		}
   591	
   592		if (bytes_mapped) {
   593			u32 new_mappings = (np << page_shift) -
   594				(user_va - round_down(user_va, 1 << page_shift));
   595	
   596			*bytes_mapped += min_t(u32, new_mappings, bcnt);
   597		}
   598	
   599		return np << (page_shift - PAGE_SHIFT);
   600	
   601	out:
   602		return ret;
   603	}
   604	

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