Hello, Anvin
You are right. Thanks!
Hello, All
Please review it again. Thanks!
From bf7506ac7e9ce0df0b915164dbb7a6d858ef2e40 Mon Sep 17 00:00:00 2001
From: jzha144 <jun.zh...@intel.com>
Date: Wed, 31 Oct 2012 08:51:18 +0800
Subject: [PATCH] When we are doing a crash dump, we still need non-E820_RAM
memory type address information in order to do I/O. so only
remove all RAM ranges which need to be dumped.
Signed-off-by: jzha144 <jun.zh...@intel.com>
---
arch/x86/kernel/e820.c | 9 +++++++++
1 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index df06ade..77be839 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -851,6 +851,15 @@ static int __init parse_memmap_opt(char *p)
* reset.
*/
saved_max_pfn = e820_end_of_ram_pfn();
+
+ /*
+ * We are doing a crash dump, so remove all RAM ranges
+ * as they are the ones that need to be dumped.
+ * We still need all non-RAM information in order to do I/O.
+ */
+ e820_remove_range(0, ULLONG_MAX, E820_RAM, 1);
+ userdef = 1;
+ return 0;
#endif
e820.nr_map = 0;
userdef = 1;
--
1.7.6
Best Regards!
Zhang, jun
-----Original Message-----
From: H. Peter Anvin [mailto:h...@zytor.com]
Sent: Wednesday, October 31, 2012 12:38 PM
To: Zhang, Jun
Cc: Thomas Gleixner; Ingo Molnar; x...@kernel.org; Andrew Morton; Fleming,
Matt; Paul Gortmaker; linux-kernel@vger.kernel.org
Subject: Re: [PATCH] To crash dump, we need keep other memory type except
E820_RAM, because other type come from BIOS or firmware is used by other
code(for example: PCI_MMCONFIG).
On 10/30/2012 08:39 PM, Zhang, Jun wrote:
> Hello, Anvin
> Thanks!
>
> Hello, all
> Next is my the latest version, please review it.
> Thanks!
You're still starting in the wrong end which is confusing for the reader.
What you probably want to say is something more like:
"We are doing a crash dump, so remove all RAM ranges as they are the ones that
need to be dumped. We still need all non-RAM information in order to do I/O."
At that point it should be pretty obvious that the patch is wrong. What if we
are *not* doing a crash dump? Just because crash dump is compiled in doesn't
mean that that is what we are doing right now.
-hpa
> From 141546c77ff7be523a9e72f5259df4a6827f2c1a Mon Sep 17 00:00:00
> 2001
> From: jzha144 <jun.zh...@intel.com>
> Date: Wed, 31 Oct 2012 08:51:18 +0800
> Subject: [PATCH] If we are doing a crash dump, we still need non-E820_RAM
> memory type address information, which come from BIOS or
> firmware. for example: PCI_MMCONFIG check this address.
>
> Signed-off-by: jzha144 <jun.zh...@intel.com>
> ---
> arch/x86/kernel/e820.c | 9 +++++++++
> 1 files changed, 9 insertions(+), 0 deletions(-)
>
> diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index
> df06ade..f8672d0 100644
> --- a/arch/x86/kernel/e820.c
> +++ b/arch/x86/kernel/e820.c
> @@ -851,6 +851,15 @@ static int __init parse_memmap_opt(char *p)
> * reset.
> */
> saved_max_pfn = e820_end_of_ram_pfn();
> +
> + /*
> + * If we are doing a crash dump, we still need non-E820_RAM
> + * memory type address information. so we only remove
> + * E820_RAM type.
> + */
> + e820_remove_range(0, ULLONG_MAX, E820_RAM, 1);
> + userdef = 1;
> + return 0;
> #endif
> e820.nr_map = 0;
> userdef = 1;
>
--
H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't
speak on their behalf.
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