From: Borislav Petkov <bp@alien8.de>
To: Shenghao Yang <me@shenghaoyang.info>
Cc: x86@kernel.org, Jonathan Corbet <corbet@lwn.net>,
"Rafael J. Wysocki" <rafael@kernel.org>,
Len Brown <lenb@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
"H. Peter Anvin" <hpa@zytor.com>,
linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-acpi@vger.kernel.org
Subject: Re: [PATCH] x86/acpi: Add acpi=spcr to use SPCR-provided default console
Date: Wed, 14 Jan 2026 16:46:56 +0100 [thread overview]
Message-ID: <20260114154656.GDaWe6cFCruAGbJbhe@fat_crate.local> (raw)
In-Reply-To: <20251228092222.130954-1-me@shenghaoyang.info>
On Sun, Dec 28, 2025 at 05:22:22PM +0800, Shenghao Yang wrote:
> Commit 0231d00082f6 ("ACPI: SPCR: Make SPCR available to x86")
> made SPCR available as an earlycon option on x86 but did not add
> it as a preferred console to avoid breaking existing setups -
No one has noticed AFAICT since 2018 (this commit's date).
Also:
/* Do not enable ACPI SPCR console by default */
acpi_parse_spcr(earlycon_acpi_spcr_enable, false);
Looks nicely conservative to me.
> users have to round trip the dumped console options
> ("SPCR: console: uart,io,0x3f8,115200") back via their
> bootloader.
I don't know what that means.
> Let users opt in so serial console configuration can be made
> automatic.
Why?
Text says:
[X86] When used with no options the early console is
determined by the ACPI SPCR table.
But the code doesn't enable the SPCR console by default.
I have no clue what this patch is trying to do.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
next prev parent reply other threads:[~2026-01-14 15:47 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-28 9:22 Shenghao Yang
2026-01-14 15:46 ` Borislav Petkov [this message]
2026-01-14 17:09 ` Shenghao Yang
2026-01-15 12:00 ` Borislav Petkov
2026-01-17 7:06 ` Shenghao Yang
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