linux-kernel - Re: [PATCH v5 5/5] x86/CPU/AMD: Print the reason for the last reset

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Message-ID: <20250430191025.GFaBJ1oQjxCuig1vS6@fat_crate.local>
Date: Wed, 30 Apr 2025 21:10:25 +0200
From: Borislav Petkov <bp@...en8.de>
To: Mario Limonciello <superm1@...nel.org>
Cc: Jean Delvare <jdelvare@...e.com>, Andi Shyti <andi.shyti@...nel.org>,
	Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>,
	Jonathan Corbet <corbet@....net>,
	Mario Limonciello <mario.limonciello@....com>,
	Yazen Ghannam <yazen.ghannam@....com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	"maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@...nel.org>,
	"H . Peter Anvin" <hpa@...or.com>,
	Shyam Sundar S K <Shyam-sundar.S-k@....com>,
	Hans de Goede <hdegoede@...hat.com>,
	"open list:DOCUMENTATION" <linux-doc@...r.kernel.org>,
	open list <linux-kernel@...r.kernel.org>,
	"open list:I2C/SMBUS CONTROLLER DRIVERS FOR PC" <linux-i2c@...r.kernel.org>,
	"open list:AMD PMC DRIVER" <platform-driver-x86@...r.kernel.org>
Subject: Re: [PATCH v5 5/5] x86/CPU/AMD: Print the reason for the last reset

On Wed, Apr 30, 2025 at 02:05:44PM -0500, Mario Limonciello wrote:
> On 4/30/2025 2:03 PM, Borislav Petkov wrote:
> > On Tue, Apr 22, 2025 at 06:48:30PM -0500, Mario Limonciello wrote:
> > > +	/* Iterate on each bit in the 'value' mask: */
> > > +	while (true) {
> > > +		bit = find_next_bit(&value, BITS_PER_LONG, bit + 1);
> > > +
> > > +		/* Reached the end of the word, no more bits: */
> > > +		if (bit >= BITS_PER_LONG) {
> > > +			if (!nr_reasons)
> > > +				pr_info("x86/amd: Previous system reset reason [0x%08lx]: Unknown\n", value);
> > > +			break;
> > > +		}
> > > +
> > > +		if (!s5_reset_reason_txt[bit])
> > > +			continue;
> > > +
> > > +		nr_reasons++;
> > > +		pr_info("x86/amd: Previous system reset reason [0x%08lx]: %s\n",
> > > +			value, s5_reset_reason_txt[bit]);
> > > +	}
> > 
> > What happened to that simpler idea:
> > 
> > https://lore.kernel.org/r/20250411125050.GEZ_kQKtYBfEMDQuXU@fat_crate.local
> > 
> 
> This one was more advantageous in that if multiple bits were set for any
> reason we could get messages for all of them printed.

I don't understand - you dump an array element for every bit now too...

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette