From: Serge Semin <fancer.lancer@gmail.com>
To: Yuan Can <yuancan@huawei.com>
Cc: jdmason@kudzu.us, dave.jiang@intel.com, allenbh@gmail.com,
ntb@lists.linux.dev
Subject: Re: [PATCH] ntb: idt: Fix error handling in idt_pci_driver_init()
Date: Thu, 9 Mar 2023 15:21:16 +0300 [thread overview]
Message-ID: <20230309122116.dd77crokt2rmmbuw@mobilestation> (raw)
In-Reply-To: <20221105094301.106276-1-yuancan@huawei.com>
On Sat, Nov 05, 2022 at 09:43:01AM +0000, Yuan Can wrote:
> A problem about ntb_hw_idt create debugfs failed is triggered with the
> following log given:
>
> [ 1236.637636] IDT PCI-E Non-Transparent Bridge Driver 2.0
> [ 1236.639292] debugfs: Directory 'ntb_hw_idt' with parent '/' already present!
>
> The reason is that idt_pci_driver_init() returns pci_register_driver()
> directly without checking its return value, if pci_register_driver()
> failed, it returns without destroy the newly created debugfs, resulting
> the debugfs of ntb_hw_idt can never be created later.
>
> idt_pci_driver_init()
> debugfs_create_dir() # create debugfs directory
> pci_register_driver()
> driver_register()
> bus_add_driver()
> priv = kzalloc(...) # OOM happened
> # return without destroy debugfs directory
>
> Fix by removing debugfs when pci_register_driver() returns error.
Indeed. Thanks for the patch.
Acked-by: Serge Semin <fancer.lancer@gmail.com>
-Serge(y)
>
> Fixes: bf2a952d31d2 ("NTB: Add IDT 89HPESxNTx PCIe-switches support")
> Signed-off-by: Yuan Can <yuancan@huawei.com>
> ---
> drivers/ntb/hw/idt/ntb_hw_idt.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/ntb/hw/idt/ntb_hw_idt.c b/drivers/ntb/hw/idt/ntb_hw_idt.c
> index 0ed6f809ff2e..51799fccf840 100644
> --- a/drivers/ntb/hw/idt/ntb_hw_idt.c
> +++ b/drivers/ntb/hw/idt/ntb_hw_idt.c
> @@ -2891,6 +2891,7 @@ static struct pci_driver idt_pci_driver = {
>
> static int __init idt_pci_driver_init(void)
> {
> + int ret;
> pr_info("%s %s\n", NTB_DESC, NTB_VER);
>
> /* Create the top DebugFS directory if the FS is initialized */
> @@ -2898,7 +2899,11 @@ static int __init idt_pci_driver_init(void)
> dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
>
> /* Register the NTB hardware driver to handle the PCI device */
> - return pci_register_driver(&idt_pci_driver);
> + ret = pci_register_driver(&idt_pci_driver);
> + if (ret)
> + debugfs_remove_recursive(dbgfs_topdir);
> +
> + return ret;
> }
> module_init(idt_pci_driver_init);
>
> --
> 2.17.1
>
prev parent reply other threads:[~2023-03-09 12:21 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-05 9:43 [PATCH] ntb: idt: Fix error handling in idt_pci_driver_init() Yuan Can
2023-03-09 12:21 ` Serge Semin [this message]
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