linux-kernel - Re: [PATCH v2 09/16] x86/mce: Unify AMD THR handler with MCA Polling

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Message-ID: <20240429134043.GPZi-jWzoVe3bJkyYX@fat_crate.local>
Date: Mon, 29 Apr 2024 15:40:43 +0200
From: Borislav Petkov <bp@...en8.de>
To: Yazen Ghannam <yazen.ghannam@....com>
Cc: linux-edac@...r.kernel.org, linux-kernel@...r.kernel.org,
	tony.luck@...el.com, x86@...nel.org, Avadhut.Naik@....com,
	John.Allen@....com
Subject: Re: [PATCH v2 09/16] x86/mce: Unify AMD THR handler with MCA Polling

On Thu, Apr 04, 2024 at 10:13:52AM -0500, Yazen Ghannam wrote:
> @@ -787,6 +793,8 @@ bool machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
>  			mce_log(&m);
>  
>  clear_it:
> +		vendor_handle_error(&m);

Wait, whaaat?

The normal polling happens periodically (each 5 mins) and you want to
reset the thresholding blocks each 5 mins?

And the code has there now:

static void reset_block(struct threshold_block *block)
{

..

        /* Reset threshold block after logging error. */
        memset(&tr, 0, sizeof(tr));
        tr.b = block;
        threshold_restart_bank(&tr);
}

but no error has been logged.

Frankly, I don't see the point for this part: polling all banks on
a thresholding interrupt makes sense. But this resetting from within the
polling doesn't make any sense.

Especially if that polling interval is user-controllable.

Thx.

-- 
Regards/Gruss,
    Boris.

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