From: Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com>
To: unlisted-recipients:; (no To-header on input)
Cc: saeed.mirzamohammadi@oracle.com,
John Donnelly <john.p.donnelly@oracle.com>,
Dave Young <dyoung@redhat.com>, Baoquan He <bhe@redhat.com>,
Vivek Goyal <vgoyal@redhat.com>, Jonathan Corbet <corbet@lwn.net>,
"Paul E. McKenney" <paulmck@kernel.org>,
Randy Dunlap <rdunlap@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
Mike Kravetz <mike.kravetz@oracle.com>,
"Guilherme G. Piccoli" <gpiccoli@canonical.com>,
Kees Cook <keescook@chromium.org>,
"Peter Zijlstra (Intel)" <peterz@infradead.org>,
Ingo Molnar <mingo@kernel.org>,
"Steven Rostedt (VMware)" <rostedt@goodmis.org>,
YiFei Zhu <yifeifz2@illinois.edu>,
Josh Poimboeuf <jpoimboe@redhat.com>,
Mike Rapoport <rppt@kernel.org>,
Masahiro Yamada <masahiroy@kernel.org>,
Sami Tolvanen <samitolvanen@google.com>,
Frederic Weisbecker <frederic@kernel.org>,
Christian Brauner <christian.brauner@ubuntu.com>,
Stephen Boyd <sboyd@kernel.org>,
Andrey Konovalov <andreyknvl@google.com>,
Colin Ian King <colin.king@canonical.com>,
kexec@lists.infradead.org, linux-doc@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH v4 1/1] kernel/crash_core: Add crashkernel=auto for vmcore creation
Date: Tue, 23 Feb 2021 09:41:50 -0800 [thread overview]
Message-ID: <20210223174153.72802-1-saeed.mirzamohammadi@oracle.com> (raw)
This adds crashkernel=auto feature to configure reserved memory for
vmcore creation. CONFIG_CRASH_AUTO_STR is defined to be set for
different kernel distributions and different archs based on their
needs.
Signed-off-by: Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com>
Signed-off-by: John Donnelly <john.p.donnelly@oracle.com>
Tested-by: John Donnelly <john.p.donnelly@oracle.com>
---
Documentation/admin-guide/kdump/kdump.rst | 3 ++-
.../admin-guide/kernel-parameters.txt | 6 ++++++
arch/Kconfig | 20 +++++++++++++++++++
kernel/crash_core.c | 7 +++++++
4 files changed, 35 insertions(+), 1 deletion(-)
diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst
index 75a9dd98e76e..ae030111e22a 100644
--- a/Documentation/admin-guide/kdump/kdump.rst
+++ b/Documentation/admin-guide/kdump/kdump.rst
@@ -285,7 +285,8 @@ This would mean:
2) if the RAM size is between 512M and 2G (exclusive), then reserve 64M
3) if the RAM size is larger than 2G, then reserve 128M
-
+Or you can use crashkernel=auto to choose the crash kernel memory size
+based on the recommended configuration set for each arch.
Boot into System Kernel
=======================
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 9e3cdb271d06..a5deda5c85fe 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -747,6 +747,12 @@
a memory unit (amount[KMG]). See also
Documentation/admin-guide/kdump/kdump.rst for an example.
+ crashkernel=auto
+ [KNL] This parameter will set the reserved memory for
+ the crash kernel based on the value of the CRASH_AUTO_STR
+ that is the best effort estimation for each arch. See also
+ arch/Kconfig for further details.
+
crashkernel=size[KMG],high
[KNL, X86-64] range could be above 4G. Allow kernel
to allocate physical memory region from top, so could
diff --git a/arch/Kconfig b/arch/Kconfig
index 24862d15f3a3..23d047548772 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -14,6 +14,26 @@ menu "General architecture-dependent options"
config CRASH_CORE
bool
+config CRASH_AUTO_STR
+ string "Memory reserved for crash kernel"
+ depends on CRASH_CORE
+ default "1G-64G:128M,64G-1T:256M,1T-:512M"
+ help
+ This configures the reserved memory dependent
+ on the value of System RAM. The syntax is:
+ crashkernel=<range1>:<size1>[,<range2>:<size2>,...][@offset]
+ range=start-[end]
+
+ For example:
+ crashkernel=512M-2G:64M,2G-:128M
+
+ This would mean:
+
+ 1) if the RAM is smaller than 512M, then don't reserve anything
+ (this is the "rescue" case)
+ 2) if the RAM size is between 512M and 2G (exclusive), then reserve 64M
+ 3) if the RAM size is larger than 2G, then reserve 128M
+
config KEXEC_CORE
select CRASH_CORE
bool
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 825284baaf46..90f9e4bb6704 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -7,6 +7,7 @@
#include <linux/crash_core.h>
#include <linux/utsname.h>
#include <linux/vmalloc.h>
+#include <linux/kexec.h>
#include <asm/page.h>
#include <asm/sections.h>
@@ -250,6 +251,12 @@ static int __init __parse_crashkernel(char *cmdline,
if (suffix)
return parse_crashkernel_suffix(ck_cmdline, crash_size,
suffix);
+#ifdef CONFIG_CRASH_AUTO_STR
+ if (strncmp(ck_cmdline, "auto", 4) == 0) {
+ ck_cmdline = CONFIG_CRASH_AUTO_STR;
+ pr_info("Using crashkernel=auto, the size chosen is a best effort estimation.\n");
+ }
+#endif
/*
* if the commandline contains a ':', then that's the extended
* syntax -- if not, it must be the classic syntax
--
2.27.0
next reply other threads:[~2021-02-23 17:45 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-23 17:41 Saeed Mirzamohammadi [this message]
2021-02-24 2:07 ` [PATCH v4 1/1] kernel/crash_core: Add crashkernel=auto for vmcore creation Baoquan He
2021-02-24 6:21 ` Kairui Song
2021-02-26 0:38 ` Dave Young
2021-03-02 23:05 ` john.p.donnelly
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=20210223174153.72802-1-saeed.mirzamohammadi@oracle.com \
--to=saeed.mirzamohammadi@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=andreyknvl@google.com \
--cc=bhe@redhat.com \
--cc=christian.brauner@ubuntu.com \
--cc=colin.king@canonical.com \
--cc=corbet@lwn.net \
--cc=dyoung@redhat.com \
--cc=frederic@kernel.org \
--cc=gpiccoli@canonical.com \
--cc=john.p.donnelly@oracle.com \
--cc=jpoimboe@redhat.com \
--cc=keescook@chromium.org \
--cc=kexec@lists.infradead.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=masahiroy@kernel.org \
--cc=mchehab+huawei@kernel.org \
--cc=mike.kravetz@oracle.com \
--cc=mingo@kernel.org \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=rdunlap@infradead.org \
--cc=rostedt@goodmis.org \
--cc=rppt@kernel.org \
--cc=samitolvanen@google.com \
--cc=sboyd@kernel.org \
--cc=tglx@linutronix.de \
--cc=vgoyal@redhat.com \
--cc=yifeifz2@illinois.edu \
/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 read-only IMAP folder(s) and NNTP newsgroup(s).