linux-kernel - Re: [PATCH 3/4] PCI: shpchp: Cleanup logging and debug wrappers

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: <20250213220453.GA135512@bhelgaas>
Date: Thu, 13 Feb 2025 16:04:53 -0600
From: Bjorn Helgaas <helgaas@...nel.org>
To: Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@...gle.com>, linux-pci@...r.kernel.org,
	Karolina Stolarek <karolina.stolarek@...cle.com>,
	linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
	Mahesh J Salgaonkar <mahesh@...ux.ibm.com>,
	Oliver O'Halloran <oohall@...il.com>
Subject: Re: [PATCH 3/4] PCI: shpchp: Cleanup logging and debug wrappers

On Mon, Dec 16, 2024 at 06:10:11PM +0200, Ilpo Järvinen wrote:
> The shpchp hotplug driver defines logging wrappers ctrl_*() and another
> set of wrappers with generic names which are just duplicates of
> existing generic printk() wrappers. Only the former are useful to
> preserve as they handle the controller dereferencing (the latter are
> also unused).
> 
> The "shpchp_debug" module parameter is used to enable debug logging.
> The generic ability to turn on/off debug prints dynamically covers this
> usecase already so there is no need to module specific debug handling.
> The ctrl_dbg() wrapper also uses a low-level pci_printk() despite
> always using KERN_DEBUG level.

I think it's great to get rid of the module param.  Can you include
a hint about how users of shpchp_debug should now enable debug prints?

The one I have in my notes is to set CONFIG_DYNAMIC_DEBUG=y and boot
with 'dyndbg="file drivers/pci/* +p"'.

> Convert ctrl_dbg() to use the pci_dbg() and remove "shpchp_debug" check
> from it.
> 
> Removing the non-ctrl variants of logging wrappers and "shpchp_debug"
> module parameter as they are no longer used.

> -#define dbg(format, arg...)						\
> -do {									\
> -	if (shpchp_debug)						\
> -		printk(KERN_DEBUG "%s: " format, MY_NAME, ## arg);	\
> -} while (0)
> -#define err(format, arg...)						\
> -	printk(KERN_ERR "%s: " format, MY_NAME, ## arg)
> -#define info(format, arg...)						\
> -	printk(KERN_INFO "%s: " format, MY_NAME, ## arg)
> -#define warn(format, arg...)						\
> -	printk(KERN_WARNING "%s: " format, MY_NAME, ## arg)

The above are unused, aren't they?  Can we make a separate patch to
remove these, for ease of describing and reviewing?

Bjorn