From: Junichi Nomura <j-nomura@ce.jp.nec.com>
To: Boris Petkov <bp@alien8.de>
Cc: Dave Young <dyoung@redhat.com>,
Chao Fan <fanc.fnst@cn.fujitsu.com>, Baoquan He <bhe@redhat.com>,
Kairui Song <kasong@redhat.com>,
"x86@kernel.org" <x86@kernel.org>,
"kexec@lists.infradead.org" <kexec@lists.infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel
Date: Thu, 11 Apr 2019 09:32:59 +0000 [thread overview]
Message-ID: <e88fda9c-bd5a-d263-cd8a-380828dd6a93@ce.jp.nec.com> (raw)
In-Reply-To: <DFC5B552-9B44-422B-8EAE-A32C24BB7A88@alien8.de>
On 4/11/19 6:21 PM, Boris Petkov wrote:
> On April 11, 2019 11:13:03 AM GMT+02:00, Junichi Nomura <j-nomura@ce.jp.nec.com> wrote:
>> On 4/11/19 5:37 PM, Borislav Petkov wrote:
>>> On Thu, Apr 11, 2019 at 08:16:45AM +0000, Junichi Nomura wrote:
>>>> kexec_get_rsdp_addr() might fail on kexec-booted kernel, e.g. if the
>>>> setup_data was invalid. In such a case, falling back to
>> efi_get_rsdp_addr()
>>>> will hit the problem of accessing invalid table pointer again.
>>>
>>> Then you need to do this:
>>>
>>> if (kexeced kernel) {
>>> addr = kexec_get_rsdp_addr();
>>> if (!addr) {
>>> /* cannot get address */
>>> return -1;
>>> }
>>>
>>> return addr;
>>> }
>>>
>>> and the calling function get_rsdp_addr() must check the return value
>> and
>>> if it is not 0, return immediately.
>>
>> Do you mean making get_rsdp_addr() like this?
>
> Does that look like what I've typed above?
No. But that's why I asked the question. Do you mean putting
the above code in efi_get_rsdp_addr()?
--
Jun'ichi Nomura, NEC Corporation / NEC Solution Innovators, Ltd.
next prev parent reply other threads:[~2019-04-11 9:33 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-08 23:10 [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel Junichi Nomura
2019-04-10 17:14 ` Borislav Petkov
2019-04-10 23:34 ` Junichi Nomura
2019-04-11 8:09 ` Borislav Petkov
2019-04-11 8:16 ` Junichi Nomura
2019-04-11 8:37 ` Borislav Petkov
2019-04-11 9:13 ` Junichi Nomura
2019-04-11 9:21 ` Boris Petkov
2019-04-11 9:32 ` Junichi Nomura [this message]
2019-04-11 9:40 ` Boris Petkov
2019-04-11 12:58 ` Borislav Petkov
2019-04-12 2:54 ` Junichi Nomura
2019-04-12 8:49 ` Borislav Petkov
2019-04-12 13:35 ` Borislav Petkov
2019-04-15 7:01 ` Junichi Nomura
2019-04-15 9:07 ` Borislav Petkov
2019-04-15 10:25 ` Borislav Petkov
2019-04-15 23:00 ` Junichi Nomura
2019-04-15 23:14 ` Junichi Nomura
2019-04-16 9:45 ` Borislav Petkov
2019-04-16 23:09 ` kexec crash on OVMF i386 + x86_64 kernel (Re: [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel) Junichi Nomura
2019-04-17 5:14 ` Dave Young
2019-04-17 17:57 ` Prakhya, Sai Praneeth
2019-04-16 9:40 ` [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel Borislav Petkov
2019-04-16 9:52 ` [PATCH] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernels Borislav Petkov
2019-04-16 10:02 ` Ingo Molnar
2019-04-16 10:31 ` Borislav Petkov
2019-04-16 11:41 ` Dave Young
2019-04-16 13:22 ` Borislav Petkov
2019-04-17 1:38 ` Dave Young
2019-04-17 4:57 ` Dave Young
2019-04-17 6:00 ` Kairui Song
2019-04-17 7:08 ` Dave Young
2019-04-17 8:22 ` Borislav Petkov
2019-04-18 1:24 ` Dave Young
2019-04-19 8:34 ` [RFC PATCH] kexec, x86/boot: map systab region in identity mapping before accessing it Kairui Song
2019-04-19 8:58 ` Baoquan He
2019-04-19 9:39 ` Kairui Song
2019-04-16 22:44 ` [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel Junichi Nomura
2019-04-17 7:02 ` Dave Young
2019-04-17 8:54 ` Borislav Petkov
2019-04-17 9:02 ` Borislav Petkov
2019-04-17 10:31 ` Chao Fan
2019-04-11 8:42 ` Baoquan He
2019-04-11 9:14 ` Junichi Nomura
2019-04-12 0:23 ` Baoquan He
2019-04-15 7:46 ` Dave Young
2019-06-06 19:22 ` [tip:x86/boot] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernels tip-bot for Junichi Nomura
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=e88fda9c-bd5a-d263-cd8a-380828dd6a93@ce.jp.nec.com \
--to=j-nomura@ce.jp.nec.com \
--cc=bhe@redhat.com \
--cc=bp@alien8.de \
--cc=dyoung@redhat.com \
--cc=fanc.fnst@cn.fujitsu.com \
--cc=kasong@redhat.com \
--cc=kexec@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=x86@kernel.org \
/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).