linux-kernel - Re: [PATCH v3 13/17] x86/mce: Unify AMD DFR handler with MCA Polling

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Message-ID: <20250508153734.GA1939543@yaz-khff2.amd.com>
Date: Thu, 8 May 2025 11:37:34 -0400
From: Yazen Ghannam <yazen.ghannam@....com>
To: Borislav Petkov <bp@...en8.de>
Cc: x86@...nel.org, Tony Luck <tony.luck@...el.com>,
	linux-kernel@...r.kernel.org, linux-edac@...r.kernel.org,
	Smita.KoralahalliChannabasappa@....com,
	Qiuxu Zhuo <qiuxu.zhuo@...el.com>
Subject: Re: [PATCH v3 13/17] x86/mce: Unify AMD DFR handler with MCA Polling

On Wed, May 07, 2025 at 11:20:42AM +0200, Borislav Petkov wrote:
> On Tue, Apr 15, 2025 at 02:55:08PM +0000, Yazen Ghannam wrote:
> > +static bool smca_should_log_poll_error(enum mcp_flags flags, struct mce_hw_err *err)
> > +{
> > +	struct mce *m = &err->m;
> > +
> > +	/*
> > +	 * If this is a deferred error found in MCA_STATUS, then clear
> > +	 * the redundant data from the MCA_DESTAT register.
> > +	 */
> > +	if (m->status & MCI_STATUS_VAL) {
> > +		if (m->status & MCI_STATUS_DEFERRED)
> > +			mce_wrmsrq(MSR_AMD64_SMCA_MCx_DESTAT(m->bank), 0);
> > +
> > +		return true;
> > +	}
> > +
> > +	/*
> > +	 * If the MCA_DESTAT register has valid data, then use
> > +	 * it as the status register.
> > +	 */
> > +	m->status = mce_rdmsrq(MSR_AMD64_SMCA_MCx_DESTAT(m->bank));
> > +
> 
> Superfluous newline.
> 

Ack.

> > +	if (!(m->status & MCI_STATUS_VAL))
> > +		return false;
> > +
> > +	/*
> > +	 * Gather all relevant data now and log the record before clearing
> > +	 * the deferred status register. This avoids needing to go back to
> > +	 * the polling function for these actions.
> > +	 */
> > +	mce_read_aux(err, m->bank);
> > +
> > +	if (m->status & MCI_STATUS_ADDRV)
> > +		m->addr = mce_rdmsrq(MSR_AMD64_SMCA_MCx_DEADDR(m->bank));
> > +
> > +	smca_extract_err_addr(m);
> > +	m->severity = mce_severity(m, NULL, NULL, false);
> > +
> > +	if (flags & MCP_QUEUE_LOG)
> > +		mce_gen_pool_add(err);
> > +	else
> > +		mce_log(err);
> 
> Except you have a function which is called "should log" which also does the
> logging.
> 
> And you have that same logging being done in machine_check_poll().
> 
> This code needs more designing.
> 

Okay, will do.

Thanks,
Yazen