From: Michael Ellerman <mpe@ellerman.id.au>
To: Hari Bathini <hbathini@linux.ibm.com>,
Andrew Morton <akpm@linux-foundation.org>
Cc: Pingfan Liu <piliu@redhat.com>,
Kexec-ml <kexec@lists.infradead.org>,
Mimi Zohar <zohar@linux.ibm.com>,
Nayna Jain <nayna@linux.ibm.com>, Petr Tesarik <ptesarik@suse.cz>,
Mahesh J Salgaonkar <mahesh@linux.ibm.com>,
Sourabh Jain <sourabhjain@linux.ibm.com>,
lkml <linux-kernel@vger.kernel.org>,
linuxppc-dev <linuxppc-dev@ozlabs.org>,
Eric Biederman <ebiederm@xmission.com>,
Thiago Jung Bauermann <bauerman@linux.ibm.com>,
Dave Young <dyoung@redhat.com>, Vivek Goyal <vgoyal@redhat.com>
Subject: Re: [RESEND PATCH v5 07/11] ppc64/kexec_file: enable early kernel's OPAL calls
Date: Wed, 29 Jul 2020 11:15:12 +1000 [thread overview]
Message-ID: <87v9i75dgf.fsf@mpe.ellerman.id.au> (raw)
In-Reply-To: <23baef6a-6ddc-572a-82c5-21a7fa441485@linux.ibm.com>
Hari Bathini <hbathini@linux.ibm.com> writes:
> On 28/07/20 7:16 pm, Michael Ellerman wrote:
>> Hari Bathini <hbathini@linux.ibm.com> writes:
>>> Kernel built with CONFIG_PPC_EARLY_DEBUG_OPAL enabled expects r8 & r9
>>> to be filled with OPAL base & entry addresses respectively. Setting
>>> these registers allows the kernel to perform OPAL calls before the
>>> device tree is parsed.
>>
>> I'm not convinced we want to do this.
>>
>> If we do it becomes part of the kexec ABI and we have to honour it into
>> the future.
>>
>> And in practice there are no non-development kernels built with OPAL early
>> debugging enabled, so it's not clear it actually helps anyone other than
>> developers.
>>
>
> Hmmm.. kexec-tools does it since commit d58ad564852c ("kexec/ppc64
> Enable early kernel's OPAL calls") for kexec_load syscall. So, we would
> be breaking kexec ABI either way, I guess.
Ugh, OK.
> Let me put this patch at the end of the series in the respin to let you
> decide whether to have it or not..
Thanks.
cheers
next prev parent reply other threads:[~2020-07-29 1:15 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-26 19:36 [RESEND PATCH v5 00/11] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
2020-07-26 19:36 ` [RESEND PATCH v5 01/11] kexec_file: allow archs to handle special regions while locating memory hole Hari Bathini
2020-07-26 19:36 ` [RESEND PATCH v5 02/11] powerpc/kexec_file: mark PPC64 specific code Hari Bathini
2020-07-26 19:37 ` [RESEND PATCH v5 03/11] powerpc/kexec_file: add helper functions for getting memory ranges Hari Bathini
2020-07-28 12:58 ` Michael Ellerman
2020-07-26 19:38 ` [RESEND PATCH v5 04/11] ppc64/kexec_file: avoid stomping memory used by special regions Hari Bathini
2020-07-26 19:38 ` [RESEND PATCH v5 05/11] powerpc/drmem: make lmb walk a bit more flexible Hari Bathini
2020-07-26 19:38 ` [RESEND PATCH v5 06/11] ppc64/kexec_file: restrict memory usage of kdump kernel Hari Bathini
2020-07-28 2:10 ` Thiago Jung Bauermann
2020-07-28 13:44 ` Michael Ellerman
2020-07-28 19:34 ` Hari Bathini
2020-07-26 19:39 ` [RESEND PATCH v5 07/11] ppc64/kexec_file: enable early kernel's OPAL calls Hari Bathini
2020-07-28 2:17 ` Thiago Jung Bauermann
2020-07-28 13:46 ` Michael Ellerman
2020-07-28 19:24 ` Hari Bathini
2020-07-29 1:15 ` Michael Ellerman [this message]
2020-07-26 19:39 ` [RESEND PATCH v5 08/11] ppc64/kexec_file: setup backup region for kdump kernel Hari Bathini
2020-07-28 2:37 ` Thiago Jung Bauermann
2020-07-28 14:11 ` Michael Ellerman
2020-07-26 19:39 ` [RESEND PATCH v5 09/11] ppc64/kexec_file: prepare elfcore header for crashing kernel Hari Bathini
2020-07-26 19:40 ` [RESEND PATCH v5 10/11] ppc64/kexec_file: add appropriate regions for memory reserve map Hari Bathini
2020-07-26 19:40 ` [RESEND PATCH v5 11/11] ppc64/kexec_file: fix kexec load failure with lack of memory hole Hari Bathini
2020-07-28 2:32 ` [RESEND PATCH v5 00/11] ppc64: enable kdump support for kexec_file_load syscall piliu
2020-07-30 6:05 ` Hari Bathini
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87v9i75dgf.fsf@mpe.ellerman.id.au \
--to=mpe@ellerman.id.au \
--cc=akpm@linux-foundation.org \
--cc=bauerman@linux.ibm.com \
--cc=dyoung@redhat.com \
--cc=ebiederm@xmission.com \
--cc=hbathini@linux.ibm.com \
--cc=kexec@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxppc-dev@ozlabs.org \
--cc=mahesh@linux.ibm.com \
--cc=nayna@linux.ibm.com \
--cc=piliu@redhat.com \
--cc=ptesarik@suse.cz \
--cc=sourabhjain@linux.ibm.com \
--cc=vgoyal@redhat.com \
--cc=zohar@linux.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).