From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lEjWG-0006Ju-T8 for kexec@lists.infradead.org; Wed, 24 Feb 2021 02:03:18 +0000 Date: Wed, 24 Feb 2021 10:03:01 +0800 From: Baoquan He Subject: Re: [PATCH v3 1/1] kernel/crash_core: Add crashkernel=auto for vmcore creation Message-ID: <20210224020301.GC3553@MiWiFi-R3L-srv> References: <20210211180814.69708-1-saeed.mirzamohammadi@oracle.com> <20210224015410.GB3553@MiWiFi-R3L-srv> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210224015410.GB3553@MiWiFi-R3L-srv> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Saeed Mirzamohammadi , Andrew Morton Cc: linux-doc@vger.kernel.org, "Peter Zijlstra (Intel)" , Christian Brauner , Ingo Molnar , Jonathan Corbet , Mauro Carvalho Chehab , Masahiro Yamada , Sami Tolvanen , Dave Young , Vivek Goyal , john.p.donnelly@oracle.com, Kees Cook , "Paul E. McKenney" , Andrey Konovalov , Frederic Weisbecker , "Guilherme G. Piccoli" , "Steven Rostedt (VMware)" , Josh Poimboeuf , Thomas Gleixner , Stephen Boyd , Randy Dunlap , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, YiFei Zhu , Mike Rapoport , Mike Kravetz On 02/24/21 at 09:54am, Baoquan He wrote: > On 02/11/21 at 10:08am, Saeed Mirzamohammadi wrote: > > 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 > > Signed-off-by: John Donnelly > > Tested-by: John Donnelly > > --- > > Documentation/admin-guide/kdump/kdump.rst | 3 ++- > > .../admin-guide/kernel-parameters.txt | 6 +++++ > > arch/Kconfig | 24 +++++++++++++++++++ > > kernel/crash_core.c | 7 ++++++ > > 4 files changed, 39 insertions(+), 1 deletion(-) > > Acked-by: Baoquan He Sorry, I just acked on wrong version of patch, please ignore this. > > > > > diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst > > index 2da65fef2a1c..e55cdc404c6b 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 7d4e523646c3..aa2099465458 100644 > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -736,6 +736,12 @@ > > 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 af14a567b493..f87c88ffa2f8 100644 > > --- a/arch/Kconfig > > +++ b/arch/Kconfig > > @@ -14,6 +14,30 @@ menu "General architecture-dependent options" > > config CRASH_CORE > > bool > > > > +if CRASH_CORE > > + > > +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=:[,:,...][@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 > > + > > +endif # CRASH_CORE > > + > > config KEXEC_CORE > > select CRASH_CORE > > bool > > diff --git a/kernel/crash_core.c b/kernel/crash_core.c > > index 106e4500fd53..ab0a2b4b1ffa 100644 > > --- a/kernel/crash_core.c > > +++ b/kernel/crash_core.c > > @@ -7,6 +7,7 @@ > > #include > > #include > > #include > > +#include > > > > #include > > #include > > @@ -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 > > _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec