LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: AKASHI Takahiro <takahiro.akashi@linaro.org>
To: James Morse <james.morse@arm.com>
Cc: catalin.marinas@arm.com, will.deacon@arm.com,
	dhowells@redhat.com, vgoyal@redhat.com,
	herbert@gondor.apana.org.au, davem@davemloft.net,
	dyoung@redhat.com, bhe@redhat.com, arnd@arndb.de,
	ard.biesheuvel@linaro.org, bhsharma@redhat.com,
	kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v9 07/11] arm64: kexec_file: add crash dump support
Date: Fri, 18 May 2018 18:58:48 +0900	[thread overview]
Message-ID: <20180518095847.GO2737@linaro.org> (raw)
In-Reply-To: <3d70c7d1-4985-a427-ecc6-a7edc84edfff@arm.com>

On Wed, May 16, 2018 at 09:34:41AM +0100, James Morse wrote:
> Hi Akashi,
> 
> On 15/05/18 18:11, James Morse wrote:
> > On 25/04/18 07:26, AKASHI Takahiro wrote:
> >> Enabling crash dump (kdump) includes
> >> * prepare contents of ELF header of a core dump file, /proc/vmcore,
> >>   using crash_prepare_elf64_headers(), and
> >> * add two device tree properties, "linux,usable-memory-range" and
> >>   "linux,elfcorehdr", which represent repsectively a memory range
> >>   to be used by crash dump kernel and the header's location
> 
> >> diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
> >> index 37c0a9dc2e47..ec674f4d267c 100644
> >> --- a/arch/arm64/kernel/machine_kexec_file.c
> >> +++ b/arch/arm64/kernel/machine_kexec_file.c
> >> @@ -76,6 +81,78 @@ int arch_kexec_walk_mem(struct kexec_buf *kbuf,
> 
> >> +static void fill_property(void *buf, u64 val64, int cells)
> >> +{
> >> +	u32 val32;
> >> +
> >> +	if (cells == 1) {
> >> +		val32 = cpu_to_fdt32((u32)val64);
> >> +		memcpy(buf, &val32, sizeof(val32));
> >> +	} else {
> > 
> >> +		memset(buf, 0, cells * sizeof(u32) - sizeof(u64));
> >> +		buf += cells * sizeof(u32) - sizeof(u64);
> > 
> > Is this trying to clear the 'top' cells and shuffle the pointer to point at the
> > 'bottom' 2? I'm pretty sure this isn't endian safe.
> 
> It came to me at 2am: this only works on big-endian, which is exactly what you
> want as that is the DT format.

Oops, I was almost tricked as I haven't tested kexec on BE
for a long time :)

Thanks,
-Takahiro AKASHI

> 
> > Do we really expect a system to have #address-cells > 2?
> 
> 
> Thanks,
> 
> James

  reply	other threads:[~2018-05-18  9:58 UTC|newest]

Thread overview: 52+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-25  6:26 [PATCH v9 00/11] arm64: kexec: add kexec_file_load() support AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 01/11] asm-generic: add kexec_file_load system call to unistd.h AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 02/11] kexec_file: make kexec_image_post_load_cleanup_default() global AKASHI Takahiro
2018-04-28  9:45   ` Dave Young
2018-05-01 17:46   ` James Morse
2018-05-07  4:40     ` AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 03/11] arm64: kexec_file: invoke the kernel without purgatory AKASHI Takahiro
2018-05-01 17:46   ` James Morse
2018-05-07  5:22     ` AKASHI Takahiro
2018-05-11 17:03       ` James Morse
2018-05-15  4:45         ` AKASHI Takahiro
2018-05-15 16:15           ` James Morse
2018-05-18  6:22             ` AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 04/11] arm64: kexec_file: allocate memory walking through memblock list AKASHI Takahiro
2018-05-01 17:46   ` James Morse
2018-05-07  5:59     ` AKASHI Takahiro
2018-05-15  4:35       ` AKASHI Takahiro
2018-05-15 16:17         ` James Morse
2018-05-17  2:10       ` Baoquan He
2018-05-17  2:15         ` Baoquan He
2018-05-17 18:04           ` James Morse
2018-05-18  1:37             ` Baoquan He
2018-05-18  5:07               ` AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 05/11] arm64: kexec_file: load initrd and device-tree AKASHI Takahiro
2018-05-15 16:20   ` James Morse
2018-05-18  7:11     ` AKASHI Takahiro
2018-05-18  7:42       ` AKASHI Takahiro
2018-05-18 15:59         ` James Morse
2018-04-25  6:26 ` [PATCH v9 06/11] arm64: kexec_file: allow for loading Image-format kernel AKASHI Takahiro
2018-05-01 17:46   ` James Morse
2018-05-07  7:21     ` AKASHI Takahiro
2018-05-11 17:07       ` James Morse
2018-05-15  5:13         ` AKASHI Takahiro
2018-05-15 17:14           ` James Morse
2018-05-21  9:32             ` AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 07/11] arm64: kexec_file: add crash dump support AKASHI Takahiro
2018-05-15 17:11   ` James Morse
2018-05-16  8:34     ` James Morse
2018-05-18  9:58       ` AKASHI Takahiro [this message]
2018-05-16 10:06     ` James Morse
2018-05-18  9:50       ` AKASHI Takahiro
2018-05-18 10:39     ` AKASHI Takahiro
2018-05-18 16:00       ` James Morse
2018-05-21  9:46         ` AKASHI Takahiro
2018-05-15 17:12   ` James Morse
2018-05-18 15:35     ` Rob Herring
2018-05-21 10:14       ` AKASHI Takahiro
2018-05-24 14:25         ` Rob Herring
2018-04-25  6:26 ` [PATCH v9 08/11] arm64: enable KEXEC_FILE config AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 09/11] include: pe.h: remove message[] from mz header definition AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 10/11] arm64: kexec_file: add kernel signature verification support AKASHI Takahiro
2018-04-25  6:26 ` [PATCH v9 11/11] arm64: kexec_file: add kaslr support AKASHI Takahiro

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=20180518095847.GO2737@linaro.org \
    --to=takahiro.akashi@linaro.org \
    --cc=ard.biesheuvel@linaro.org \
    --cc=arnd@arndb.de \
    --cc=bhe@redhat.com \
    --cc=bhsharma@redhat.com \
    --cc=catalin.marinas@arm.com \
    --cc=davem@davemloft.net \
    --cc=dhowells@redhat.com \
    --cc=dyoung@redhat.com \
    --cc=herbert@gondor.apana.org.au \
    --cc=james.morse@arm.com \
    --cc=kexec@lists.infradead.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=vgoyal@redhat.com \
    --cc=will.deacon@arm.com \
    --subject='Re: [PATCH v9 07/11] arm64: kexec_file: add crash dump support' \
    /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

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).