From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-184.mta0.migadu.com (out-184.mta0.migadu.com [91.218.175.184]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3FEE61448D5 for ; Sun, 25 May 2025 05:22:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.184 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748150569; cv=none; b=biPZYGV0MjDBoj8KlO32rbB4x+RJJOawjl8zZ8ePV3OTvm8gEsoGxSnh/GIh99XuRYuups+RMnIwNA0NAsyEj9tqntocfPbb9diDC01Z/jDcjssO8W+cuhkNWa4G3Nk1L+bFqmV8DBLk3wkioDRdT24yQdZzzzrTr88SoSF+RTE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748150569; c=relaxed/simple; bh=Y0cKLo2CRuRqesXQHK7UPNsQP2uYigpqB/5Xc7bhblk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Bcjl2S5w8i2MIs+y6LbpqdcceyfC0pIF5AW4Wri9rSO9HqrhXf/oIr1Eu08UsAklWP+H4YoCJK9OlY0xImMyuLv786k2oRMxGF9A3E9CFFBYPPgX5l6ScDwQqS6WATcLWnEwfeagmNQ6pnCaB5PHxyPrPWMZNYF9RgKA1+dsTtQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=BZm6saAM; arc=none smtp.client-ip=91.218.175.184 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="BZm6saAM" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1748150563; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ePdy++AUzSGQt0jdpQhw2NDW+rHZoCino5XFKMdBg8U=; b=BZm6saAM54E6afEmIAR3+9ovXEHEjRhUAYo3Ru3Np1H78iHhMCVFbMFzLs0trouNyHDt3Z +H5/v46+b94QXVBMuSqKoNIv0xJt3cmxxNGYenUQv7rBVDp7VcANbVdavGcoQbnuHGTvg/ r0BtzsW2Jw+Na1FWLOsdd9rDGBkl/tY= Date: Sun, 25 May 2025 07:22:40 +0200 Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH for-next v3] RDMA/core: Avoid hmm_dma_map_alloc() for virtual DMA devices To: Daisuke Matsuda , linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, leon@kernel.org, jgg@ziepe.ca, zyjzyj2000@gmail.com Cc: hch@infradead.org References: <20250524144328.4361-1-dskmtsd@gmail.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Zhu Yanjun In-Reply-To: <20250524144328.4361-1-dskmtsd@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 2025/5/24 16:43, Daisuke Matsuda 写道: > Drivers such as rxe, which use virtual DMA, must not call into the DMA > mapping core since they lack physical DMA capabilities. Otherwise, a NULL > pointer dereference is observed as shown below. This patch ensures the RDMA > core handles virtual and physical DMA paths appropriately. > > This fixes the following kernel oops: > > BUG: kernel NULL pointer dereference, address: 00000000000002fc > #PF: supervisor read access in kernel mode > #PF: error_code(0x0000) - not-present page > PGD 1028eb067 P4D 1028eb067 PUD 105da0067 PMD 0 > Oops: Oops: 0000 [#1] SMP NOPTI > CPU: 3 UID: 1000 PID: 1854 Comm: python3 Tainted: G W 6.15.0-rc1+ #11 PREEMPT(voluntary) > Tainted: [W]=WARN > Hardware name: Trigkey Key N/Key N, BIOS KEYN101 09/02/2024 > RIP: 0010:hmm_dma_map_alloc+0x25/0x100 > Code: 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 49 89 d6 49 c1 e6 0c 41 55 41 54 53 49 39 ce 0f 82 c6 00 00 00 49 89 fc 87 fc 02 00 00 20 0f 84 af 00 00 00 49 89 f5 48 89 d3 49 89 cf > RSP: 0018:ffffd3d3420eb830 EFLAGS: 00010246 > RAX: 0000000000001000 RBX: ffff8b727c7f7400 RCX: 0000000000001000 > RDX: 0000000000000001 RSI: ffff8b727c7f74b0 RDI: 0000000000000000 > RBP: ffffd3d3420eb858 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 > R13: 00007262a622a000 R14: 0000000000001000 R15: ffff8b727c7f74b0 > FS: 00007262a62a1080(0000) GS:ffff8b762ac3e000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00000000000002fc CR3: 000000010a1f0004 CR4: 0000000000f72ef0 > PKRU: 55555554 > Call Trace: > > ib_init_umem_odp+0xb6/0x110 [ib_uverbs] > ib_umem_odp_get+0xf0/0x150 [ib_uverbs] > rxe_odp_mr_init_user+0x71/0x170 [rdma_rxe] > rxe_reg_user_mr+0x217/0x2e0 [rdma_rxe] > ib_uverbs_reg_mr+0x19e/0x2e0 [ib_uverbs] > ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0xd9/0x150 [ib_uverbs] > ib_uverbs_cmd_verbs+0xd19/0xee0 [ib_uverbs] > ? mmap_region+0x63/0xd0 > ? __pfx_ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0x10/0x10 [ib_uverbs] > ib_uverbs_ioctl+0xba/0x130 [ib_uverbs] > __x64_sys_ioctl+0xa4/0xe0 > x64_sys_call+0x1178/0x2660 > do_syscall_64+0x7e/0x170 > ? syscall_exit_to_user_mode+0x4e/0x250 > ? do_syscall_64+0x8a/0x170 > ? do_syscall_64+0x8a/0x170 > ? syscall_exit_to_user_mode+0x4e/0x250 > ? do_syscall_64+0x8a/0x170 > ? syscall_exit_to_user_mode+0x4e/0x250 > ? do_syscall_64+0x8a/0x170 > ? do_user_addr_fault+0x1d2/0x8d0 > ? irqentry_exit_to_user_mode+0x43/0x250 > ? irqentry_exit+0x43/0x50 > ? exc_page_fault+0x93/0x1d0 > entry_SYSCALL_64_after_hwframe+0x76/0x7e > RIP: 0033:0x7262a6124ded > Code: 04 25 28 00 00 00 48 89 45 c8 31 c0 48 8d 45 10 c7 45 b0 10 00 00 00 48 89 45 b8 48 8d 45 d0 48 89 45 c0 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1a 48 8b 45 c8 64 48 2b 04 25 28 00 00 00 > RSP: 002b:00007fffd08c3960 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 00007fffd08c39f0 RCX: 00007262a6124ded > RDX: 00007fffd08c3a10 RSI: 00000000c0181b01 RDI: 0000000000000007 > RBP: 00007fffd08c39b0 R08: 0000000014107820 R09: 00007fffd08c3b44 > R10: 000000000000000c R11: 0000000000000246 R12: 00007fffd08c3b44 > R13: 000000000000000c R14: 00007fffd08c3b58 R15: 0000000014107960 > > > Fixes: 1efe8c0670d6 ("RDMA/core: Convert UMEM ODP DMA mapping to caching IOVA and page linkage") > Closes: https://lore.kernel.org/all/3e8f343f-7d66-4f7a-9f08-3910623e322f@gmail.com/ > Signed-off-by: Daisuke Matsuda I tried to apply this commit to the following rdma branch. But I failed. The error is as below: " Applying: RDMA/core: Avoid hmm_dma_map_alloc() for virtual DMA devices error: patch failed: drivers/infiniband/core/umem_odp.c:75 error: drivers/infiniband/core/umem_odp.c: patch does not apply Patch failed at 0001 RDMA/core: Avoid hmm_dma_map_alloc() for virtual DMA devices hint: Use 'git am --show-current-patch=diff' to see the failed patch When you have resolved this problem, run "git am --continue". If you prefer to skip this patch, run "git am --skip" instead. To restore the original branch and stop patching, run "git am --abort". " The remote branch is remotes/rdma/rdma-next The head commit is 3b6a1e410c7f RDMA/mlx5: Fix CC counters query for MPV I am not sure if I use the correct repository and branch or not. Best Regards, Zhu Yanjun > --- > drivers/infiniband/core/device.c | 17 +++++++++++++++++ > drivers/infiniband/core/umem_odp.c | 11 ++++++++--- > include/rdma/ib_verbs.h | 4 ++++ > 3 files changed, 29 insertions(+), 3 deletions(-) > > diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c > index b4e3e4beb7f4..abb8fed292c0 100644 > --- a/drivers/infiniband/core/device.c > +++ b/drivers/infiniband/core/device.c > @@ -2864,6 +2864,23 @@ int ib_dma_virt_map_sg(struct ib_device *dev, struct scatterlist *sg, int nents) > return nents; > } > EXPORT_SYMBOL(ib_dma_virt_map_sg); > +int ib_dma_virt_map_alloc(struct hmm_dma_map *map, size_t nr_entries, > + size_t dma_entry_size) > +{ > + if (!(nr_entries * PAGE_SIZE / dma_entry_size)) > + return -EINVAL; > + > + map->dma_entry_size = dma_entry_size; > + map->pfn_list = kvcalloc(nr_entries, sizeof(*map->pfn_list), > + GFP_KERNEL | __GFP_NOWARN); > + if (!map->pfn_list) > + return -ENOMEM; > + > + map->dma_list = NULL; > + > + return 0; > +} > +EXPORT_SYMBOL(ib_dma_virt_map_alloc); > #endif /* CONFIG_INFINIBAND_VIRT_DMA */ > > static const struct rdma_nl_cbs ibnl_ls_cb_table[RDMA_NL_LS_NUM_OPS] = { > diff --git a/drivers/infiniband/core/umem_odp.c b/drivers/infiniband/core/umem_odp.c > index 51d518989914..a5b17be0894a 100644 > --- a/drivers/infiniband/core/umem_odp.c > +++ b/drivers/infiniband/core/umem_odp.c > @@ -75,9 +75,14 @@ static int ib_init_umem_odp(struct ib_umem_odp *umem_odp, > if (unlikely(end < page_size)) > return -EOVERFLOW; > > - ret = hmm_dma_map_alloc(dev->dma_device, &umem_odp->map, > - (end - start) >> PAGE_SHIFT, > - 1 << umem_odp->page_shift); > + if (ib_uses_virt_dma(dev)) > + ret = ib_dma_virt_map_alloc(&umem_odp->map, > + (end - start) >> PAGE_SHIFT, > + 1 << umem_odp->page_shift); > + else > + ret = hmm_dma_map_alloc(dev->dma_device, &umem_odp->map, > + (end - start) >> PAGE_SHIFT, > + 1 << umem_odp->page_shift); > if (ret) > return ret; > > diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h > index b06a0ed81bdd..9ea41f288736 100644 > --- a/include/rdma/ib_verbs.h > +++ b/include/rdma/ib_verbs.h > @@ -36,6 +36,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -4221,6 +4222,9 @@ static inline void ib_dma_unmap_sg_attrs(struct ib_device *dev, > dma_attrs); > } > > +int ib_dma_virt_map_alloc(struct hmm_dma_map *map, size_t nr_entries, > + size_t dma_entry_size); > + > /** > * ib_dma_map_sgtable_attrs - Map a scatter/gather table to DMA addresses > * @dev: The device for which the DMA addresses are to be created