linux-trace-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	"Liam R. Howlett" <Liam.Howlett@oracle.com>,
	Vlastimil Babka <vbabka@suse.cz>,
	Lorenzo Stoakes <lstoakes@gmail.com>,
	linux-mm@kvack.org, Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Kees Cook <keescook@chromium.org>,
	Tony Luck <tony.luck@intel.com>,
	"Guilherme G. Piccoli" <gpiccoli@igalia.com>,
	linux-hardening@vger.kernel.org,
	Guenter Roeck <linux@roeck-us.net>,
	Ross Zwisler <zwisler@google.com>,
	wklin@google.com,
	Vineeth Remanan Pillai <vineeth@bitbyteword.org>,
	Joel Fernandes <joel@joelfernandes.org>,
	Suleiman Souhlal <suleiman@google.com>,
	Linus Torvalds <torvalds@linuxfoundation.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>
Subject: [POC][RFC][PATCH 2/2] pstore/ramoops: Add ramoops.mem_name= command line option
Date: Tue, 09 Apr 2024 17:02:56 -0400	[thread overview]
Message-ID: <20240409211351.234897475@goodmis.org> (raw)
In-Reply-To: 20240409210254.660888920@goodmis.org

From: "Steven Rostedt (Google)" <rostedt@goodmis.org>

Add a method to find a region specified by memmap=nn*align:name for
ramoops. Adding a kernel command line parameter:

  memmap=12M*4096:oops ramoops.mem_name=oops

Will use the size and location defined by the memmap parameter where it
finds the memory and labels it "oops". The "oops" in the ramoops option
is used to search for it.

This allows for arbitrary RAM to be used for ramoops if it is known that
the memory is not cleared on kernel crashes or soft reboots.

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 fs/pstore/ram.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index b1a455f42e93..c200388399fb 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -50,6 +50,11 @@ module_param_hw(mem_address, ullong, other, 0400);
 MODULE_PARM_DESC(mem_address,
 		"start of reserved RAM used to store oops/panic logs");
 
+static char *mem_name;
+module_param_named(mem_name, mem_name, charp, 0400);
+MODULE_PARM_DESC(mem_name,
+		"name of kernel param that holds addr (builtin only)");
+
 static ulong mem_size;
 module_param(mem_size, ulong, 0400);
 MODULE_PARM_DESC(mem_size,
@@ -914,6 +919,19 @@ static void __init ramoops_register_dummy(void)
 {
 	struct ramoops_platform_data pdata;
 
+#ifndef MODULE
+	/* Only allowed when builtin */
+	if (mem_name) {
+		u64 start;
+		u64 size;
+
+		if (memmap_named(mem_name, &start, &size)) {
+			mem_address = start;
+			mem_size = size;
+		}
+	}
+#endif
+
 	/*
 	 * Prepare a dummy platform data structure to carry the module
 	 * parameters. If mem_size isn't set, then there are no module
-- 
2.43.0



  parent reply	other threads:[~2024-04-09 21:11 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-09 21:02 [POC][RFC][PATCH 0/2] pstore/mm/x86: Add wildcard memmap to map pstore consistently Steven Rostedt
2024-04-09 21:02 ` [POC][RFC][PATCH 1/2] mm/x86: Add wildcard * option as memmap=nn*align:name Steven Rostedt
2024-04-09 22:23   ` Kees Cook
2024-04-09 23:11     ` Steven Rostedt
2024-04-09 23:41       ` Kees Cook
2024-04-12 20:59         ` Mike Rapoport
2024-04-12 22:19           ` Steven Rostedt
2024-04-15 17:22             ` Kees Cook
2024-05-01 14:57               ` Mike Rapoport
2024-05-06 10:38                 ` Ard Biesheuvel
2024-05-08 23:23                   ` Steven Rostedt
2024-04-09 21:02 ` Steven Rostedt [this message]
2024-04-09 22:18   ` [POC][RFC][PATCH 2/2] pstore/ramoops: Add ramoops.mem_name= command line option Kees Cook
2024-04-09 23:14     ` Steven Rostedt
2024-04-09 21:23 ` [POC][RFC][PATCH 0/2] pstore/mm/x86: Add wildcard memmap to map pstore consistently Steven Rostedt
2024-04-09 22:19   ` Kees Cook
2024-04-09 22:25     ` Luck, Tony
2024-04-09 22:41       ` Joel Fernandes
2024-04-09 23:16       ` Steven Rostedt
2024-04-09 23:37       ` Kees Cook
2024-04-09 23:52         ` Luck, Tony
2024-04-11 19:11       ` Guilherme G. Piccoli
2024-04-11 19:40         ` Steven Rostedt
2024-04-12 12:17           ` Guilherme G. Piccoli
2024-04-12 17:22             ` Steven Rostedt
2024-05-01 14:45               ` Mike Rapoport
2024-05-01 14:54                 ` Steven Rostedt
2024-05-01 15:30                   ` Mike Rapoport
2024-05-01 16:09                     ` Steven Rostedt
2024-05-01 16:11                       ` Mike Rapoport
2024-05-09  4:00                     ` Steven Rostedt
2024-05-09 17:31                       ` Steven Rostedt
2024-05-09 20:24                         ` Mike Rapoport
2024-05-09 20:33                           ` Steven Rostedt

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=20240409211351.234897475@goodmis.org \
    --to=rostedt@goodmis.org \
    --cc=Liam.Howlett@oracle.com \
    --cc=akpm@linux-foundation.org \
    --cc=bp@alien8.de \
    --cc=catalin.marinas@arm.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=gpiccoli@igalia.com \
    --cc=hpa@zytor.com \
    --cc=joel@joelfernandes.org \
    --cc=keescook@chromium.org \
    --cc=linux-hardening@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-trace-kernel@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=lstoakes@gmail.com \
    --cc=mark.rutland@arm.com \
    --cc=mathieu.desnoyers@efficios.com \
    --cc=mhiramat@kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=suleiman@google.com \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --cc=torvalds@linuxfoundation.org \
    --cc=vbabka@suse.cz \
    --cc=vineeth@bitbyteword.org \
    --cc=will@kernel.org \
    --cc=wklin@google.com \
    --cc=x86@kernel.org \
    --cc=zwisler@google.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 read-only IMAP folder(s) and NNTP newsgroup(s).