From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 6DE3337997E; Wed, 23 Sep 2026 14:30:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790173837; cv=none; b=S9NjofeYEY73A6Luqs2MqruXo69W20CwpVGp5VDE6Cvsr6mlrVMCe/2e+3YFh/qOGIcyOSdL+4h1uxgXp4yKrtbDH0tYfR6TLy2iyZaGsDZh3XMCqar5C960FPCsGeD6TnSBsMzrw80WX5gmFrxBtFhAursEIblK1Lc61IAVQPE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790173837; c=relaxed/simple; bh=UaNKFKT7LUA6HSSmxhxnAkdZ5GWw3m40s+4iQbluNfE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aHlQsSgWVL5Hwje5SxvX8oQgWUi+q1kqsEoK3k6gGNA+YDJpW8wHYFZiYsKkRjyqkzmfG3O77wk9CoeRN8HfikwOJjYC51txiFboAZ67G5YSh4MQ0txGog5qKv4i8Aqkd+5dwX+5UP9sk+d24ZVYkIWwpEDz+MBVVlP2TrK49+k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VqL5FsqT; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="VqL5FsqT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C7D611F000FF; Wed, 23 Sep 2026 14:30:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790173836; bh=L78w2mWekIKNl5yzQc4N2rnSFSsohu3NU89Zv3Rz+s0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=VqL5FsqTmTid3KBIqVwsEuQrZcfesL7aqJBsCzsgVybs4rYRljr0wWB7Oo52U+gX9 1UtVV+xc/NQK59kWFTXF6A1JwG3P2uaO23Bq8rSfb/2cX3fIsQOvQU6KlwI8xEjCfM +LngWk5FUW01SeNv4/Vx03OxHKPqUpMaFzKqEVHM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Shuhei Takeshita , Leon Romanovsky Subject: [PATCH 7.2 332/438] IB/hfi1: Fix the PIO_CRED credit-return mmap Date: Wed, 23 Sep 2026 16:05:53 +0200 Message-ID: <20260923140653.415908629@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140644.756254324@linuxfoundation.org> References: <20260923140644.756254324@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shuhei Takeshita commit 62f0f34fbd2b2d5653d33d3b9d42fdcabb1c0101 upstream. hfi1_file_mmap()'s PIO_CRED case must hand user space the single credit-return page that holds this context's entry. That page is the second or third page of the per-node credit-return allocation once the hardware send context index reaches 64 or 128, so the failure below is intermittent: when the entry lands on the first page the offset is zero and everything works. Two things are wrong. First, cr_page_offset is a byte offset but .va is a struct credit_return *, so adding it is pointer arithmetic and scales the offset by sizeof(struct credit_return) == 64. memvirt then lands 256 KiB or 512 KiB past a 10240-byte allocation. With an IOMMU translating, that address is inside the vmalloc range but in no vm_area, so dma_mmap_coherent() -> iommu_dma_mmap() finds no pages, vmalloc_to_pfn() returns page_to_pfn(NULL), and remap_pfn_range() installs a frame above MAXPHYADDR. The first user read then takes: psm2_ep_open_pr: Corrupted page table at address 7a14d007e000 PGD 800000013886a067 P4D 800000013886a067 PUD 13886b067 PMD 13886c067 PTE 800049168e911235 Oops: Bad pagetable: 000d [#1] SMP PTI Second, and still wrong once the arithmetic is corrected, dma_mmap_coherent() describes a whole coherent buffer and selects the page within it with vma->vm_pgoff. Offsetting cpu_addr has no effect: for a vmap'd allocation iommu_dma_mmap() uses cpu_addr only to locate the vm_area and then maps pages[vm_pgoff], which hfi1_file_mmap() has just set to 0. User space therefore always receives the first credit-return page, every credit read is for the wrong context, and send PIO stalls forever. Use the DMA API as intended: pass the base of the allocation with its full length and select the page with vm_pgoff. A separate length is needed because memlen must keep describing the VMA for the existing size check. The dma-direct path stays correct as well, since dma_direct_mmap() adds the same vm_pgoff to the base pfn. Tested on a Dell T7610 (Xeon E5-2650 v2, Intel IOMMU in DMA-FQ mode) against a Threadripper PRO 3995WX peer, both Omni-Path 100. Before this change psm2_ep_open() Oopses the kernel; with only the arithmetic corrected psm2_ep_open() succeeds but any transfer that uses send PIO hangs, PSM2_SDMA=2 (send PIO disabled) completing normally while PSM2_SDMA=0 (send PIO only) hangs every time. With this change send PIO, send DMA and the default mixed mode all work. Fixes: 1ec82317a1da ("IB/hfi1: Use dma_mmap_coherent for matching buffers") Cc: stable@vger.kernel.org Signed-off-by: Shuhei Takeshita Link: https://patch.msgid.link/20260809032743.2671579-3-jyohuku.alterego@gmail.com Signed-off-by: Leon Romanovsky Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/hfi1/file_ops.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) --- a/drivers/infiniband/hw/hfi1/file_ops.c +++ b/drivers/infiniband/hw/hfi1/file_ops.c @@ -326,6 +326,7 @@ static int hfi1_file_mmap(struct file *f void *memvirt = NULL; dma_addr_t memdma = 0; u8 subctxt, mapio = 0, vmf = 0, type; + size_t memdmalen = 0; ssize_t memlen = 0; int ret = 0; u16 ctxt; @@ -371,7 +372,9 @@ static int hfi1_file_mmap(struct file *f mapio = 1; break; case PIO_CRED: { + struct credit_return_base *cr = &dd->cr_base[uctxt->sc->node]; u64 cr_page_offset; + if (flags & VM_WRITE) { ret = -EPERM; goto done; @@ -381,11 +384,18 @@ static int hfi1_file_mmap(struct file *f * second or third page allocated for credit returns (if number * of enabled contexts > 64 and 128 respectively). */ - cr_page_offset = ((u64)uctxt->sc->hw_free - - (u64)dd->cr_base[uctxt->sc->node].va) & + cr_page_offset = ((u64)uctxt->sc->hw_free - (u64)cr->va) & PAGE_MASK; - memvirt = dd->cr_base[uctxt->sc->node].va + cr_page_offset; - memdma = dd->cr_base[uctxt->sc->node].dma + cr_page_offset; + /* + * dma_mmap_coherent() describes the whole coherent buffer and + * selects the page within it with vma->vm_pgoff, so pass the + * base of the allocation and its length and let vm_pgoff pick + * the page. + */ + vma->vm_pgoff = cr_page_offset >> PAGE_SHIFT; + memvirt = cr->va; + memdma = cr->dma; + memdmalen = TXE_NUM_CONTEXTS * sizeof(struct credit_return); memlen = PAGE_SIZE; flags &= ~VM_MAYWRITE; flags |= VM_DONTCOPY | VM_DONTEXPAND; @@ -567,7 +577,8 @@ static int hfi1_file_mmap(struct file *f ret = 0; } else if (memdma) { ret = dma_mmap_coherent(&dd->pcidev->dev, vma, - memvirt, memdma, memlen); + memvirt, memdma, + memdmalen ? memdmalen : memlen); } else if (mapio) { ret = io_remap_pfn_range(vma, vma->vm_start, PFN_DOWN(memaddr),