linux-kernel - [PATCH v2 1/3] ntb_hw_amd: Remove redundant pci_clear

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 24 Mar 2023 09:32:18 +0800
From:   Cai Huoqing <cai.huoqing@...ux.dev>
To:     cai.huoqing@...ux.dev
Cc:     Sanjay R Mehta <sanju.mehta@....com>,
        Shyam Sundar S K <Shyam-sundar.S-k@....com>,
        Jon Mason <jdmason@...zu.us>,
        Dave Jiang <dave.jiang@...el.com>,
        Allen Hubbe <allenbh@...il.com>, Frank Li <Frank.Li@....com>,
        ntb@...ts.linux.dev, linux-kernel@...r.kernel.org
Subject: [PATCH v2 1/3] ntb_hw_amd: Remove redundant pci_clear_master

Remove pci_clear_master to simplify the code,
the bus-mastering is also cleared in do_pci_disable_device,
like this:
./drivers/pci/pci.c:2197
static void do_pci_disable_device(struct pci_dev *dev)
{
	u16 pci_command;

	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
	if (pci_command & PCI_COMMAND_MASTER) {
		pci_command &= ~PCI_COMMAND_MASTER;
		pci_write_config_word(dev, PCI_COMMAND, pci_command);
	}

	pcibios_disable_device(dev);
}.
And dev->is_busmaster is set to 0 in pci_disable_device.

Signed-off-by: Cai Huoqing <cai.huoqing@...ux.dev>
---
v1->v2: No change
v1 link:
	https://lore.kernel.org/lkml/20230323115336.12986-1-cai.huoqing@linux.dev/

 drivers/ntb/hw/amd/ntb_hw_amd.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.c b/drivers/ntb/hw/amd/ntb_hw_amd.c
index 730f2103b91d..855ff65f64a5 100644
--- a/drivers/ntb/hw/amd/ntb_hw_amd.c
+++ b/drivers/ntb/hw/amd/ntb_hw_amd.c
@@ -1194,7 +1194,6 @@ static int amd_ntb_init_pci(struct amd_ntb_dev *ndev,
 	return 0;
 
 err_dma_mask:
-	pci_clear_master(pdev);
 	pci_release_regions(pdev);
 err_pci_regions:
 	pci_disable_device(pdev);
@@ -1209,7 +1208,6 @@ static void amd_ntb_deinit_pci(struct amd_ntb_dev *ndev)
 
 	pci_iounmap(pdev, ndev->self_mmio);
 
-	pci_clear_master(pdev);
 	pci_release_regions(pdev);
 	pci_disable_device(pdev);
 	pci_set_drvdata(pdev, NULL);
-- 
2.34.1