linux-kernel - Re: [patch V4 05/14] PCI/MSI: Use guard(msi_desc

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

Message-ID: <20250319170816.GA1046112@bhelgaas>
Date: Wed, 19 Mar 2025 12:08:16 -0500
From: Bjorn Helgaas <helgaas@...nel.org>
To: Thomas Gleixner <tglx@...utronix.de>
Cc: LKML <linux-kernel@...r.kernel.org>, Marc Zyngier <maz@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Jonathan Cameron <Jonathan.Cameron@...wei.com>,
	Nishanth Menon <nm@...com>, Dhruva Gole <d-gole@...com>,
	Tero Kristo <kristo@...nel.org>,
	Santosh Shilimkar <ssantosh@...nel.org>,
	Logan Gunthorpe <logang@...tatee.com>,
	Dave Jiang <dave.jiang@...el.com>, Jon Mason <jdmason@...zu.us>,
	Allen Hubbe <allenbh@...il.com>, ntb@...ts.linux.dev,
	Michael Kelley <mhklinux@...look.com>, Wei Liu <wei.liu@...nel.org>,
	Bjorn Helgaas <bhelgaas@...gle.com>,
	Haiyang Zhang <haiyangz@...rosoft.com>,
	linux-hyperv@...r.kernel.org, linux-pci@...r.kernel.org,
	Wei Huang <wei.huang2@....com>,
	Manivannan Sadhasivam <manivannan.sadhasivam@...aro.org>,
	"James E.J. Bottomley" <James.Bottomley@...senpartnership.com>,
	"Martin K. Petersen" <martin.petersen@...cle.com>,
	linux-scsi@...r.kernel.org,
	Jonathan Cameron <Jonathan.Cameron@...ei.com>
Subject: Re: [patch V4 05/14] PCI/MSI: Use guard(msi_desc_lock) where
 applicable

On Wed, Mar 19, 2025 at 11:56:47AM +0100, Thomas Gleixner wrote:
> Convert the trivial cases of msi_desc_lock/unlock() pairs.
> 
> No functional change.
> 
> Signed-off-by: Thomas Gleixner <tglx@...utronix.de>

Acked-by: Bjorn Helgaas <bhelgaas@...gle.com>

> ---
> V4: Split out from the previous combo patch
> ---
>  drivers/pci/msi/api.c |    6 ++----
>  drivers/pci/msi/msi.c |   12 ++++++------
>  2 files changed, 8 insertions(+), 10 deletions(-)
> 
> --- a/drivers/pci/msi/api.c
> +++ b/drivers/pci/msi/api.c
> @@ -53,10 +53,9 @@ void pci_disable_msi(struct pci_dev *dev
>  	if (!pci_msi_enabled() || !dev || !dev->msi_enabled)
>  		return;
>  
> -	msi_lock_descs(&dev->dev);
> +	guard(msi_descs_lock)(&dev->dev);
>  	pci_msi_shutdown(dev);
>  	pci_free_msi_irqs(dev);
> -	msi_unlock_descs(&dev->dev);
>  }
>  EXPORT_SYMBOL(pci_disable_msi);
>  
> @@ -196,10 +195,9 @@ void pci_disable_msix(struct pci_dev *de
>  	if (!pci_msi_enabled() || !dev || !dev->msix_enabled)
>  		return;
>  
> -	msi_lock_descs(&dev->dev);
> +	guard(msi_descs_lock)(&dev->dev);
>  	pci_msix_shutdown(dev);
>  	pci_free_msi_irqs(dev);
> -	msi_unlock_descs(&dev->dev);
>  }
>  EXPORT_SYMBOL(pci_disable_msix);
>  
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -871,13 +871,13 @@ void __pci_restore_msix_state(struct pci
>  
>  	write_msg = arch_restore_msi_irqs(dev);
>  
> -	msi_lock_descs(&dev->dev);
> -	msi_for_each_desc(entry, &dev->dev, MSI_DESC_ALL) {
> -		if (write_msg)
> -			__pci_write_msi_msg(entry, &entry->msg);
> -		pci_msix_write_vector_ctrl(entry, entry->pci.msix_ctrl);
> +	scoped_guard (msi_descs_lock, &dev->dev) {
> +		msi_for_each_desc(entry, &dev->dev, MSI_DESC_ALL) {
> +			if (write_msg)
> +				__pci_write_msi_msg(entry, &entry->msg);
> +			pci_msix_write_vector_ctrl(entry, entry->pci.msix_ctrl);
> +		}
>  	}
> -	msi_unlock_descs(&dev->dev);
>  
>  	pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
>  }
>