[LEDE-DEV] [OpenWrt-Devel] Using kdump... persistent logs, etc.

[Philip Prindeville]

Looks like it got changed here:


commit 749918911d35613f8bf7852d2a91f78ff625739e
Author: Felix Fietkau <nbd at nbd.name>
Date:   Fri Jan 13 14:48:25 2017 +0100

    x86: disable crashlog
    
    It could cause crashes with some forms of virtualization, and it is
    unlikely to work properly with most systems.
    It's safer to just disable it.
    
    Signed-off-by: Felix Fietkau <nbd at nbd.name>

diff --git a/config/Config-kernel.in b/config/Config-kernel.in
index 3f30013..a4c46f5 100644
--- a/config/Config-kernel.in
+++ b/config/Config-kernel.in
@@ -26,7 +26,7 @@ config KERNEL_PRINTK
 
 config KERNEL_CRASHLOG
        bool "Crash logging"
-       depends on !(arm || powerpc || sparc || TARGET_uml)
+       depends on !(arm || powerpc || sparc || TARGET_uml || i386 || x86_64)
        default y
 
 config KERNEL_SWAP



I must have missed the discussion about this.

I’m not using virtualization, but I’m definitely seeing crashing without it.

Can we get more details on "and it is unlikely to work properly with most systems”?

-Philip



> On Mar 3, 2017, at 12:23 AM, Syrone Wong <wong.syrone at gmail.com> wrote:
> 
> depends on !(arm || powerpc || sparc || TARGET_uml || i386 || x86_64)
> 
> x86_64 is disabled by default. You may want to enable it yourself. I
> don't know why.
> 
> 
> Best Regards,
> Syrone Wong
> 
> 
> On Fri, Mar 3, 2017 at 2:31 PM, Philip Prindeville
> <philipp_subx at redfish-solutions.com> wrote:
>> I built an x86_64 image and turned on crash logging, and then forced a crash with:
>> 
>> echo c >/proc/sysrq-trigger
>> 
>> it rebooted, but when it did there was nothing in /sys/kernel/debug/ (i.e. no crashlog file).
>> 
>> What am I missing?  Does this not work with x86_64?
>> 
>> -Philip
>> 
>> 
>>> On Feb 23, 2017, at 10:27 AM, Philip Prindeville <philipp_subx at redfish-solutions.com> wrote:
>>> 
>>> Thanks for that.
>>> 
>>> 
>>>> On Feb 22, 2017, at 11:44 PM, Syrone Wong <wong.syrone at gmail.com> wrote:
>>>> 
>>>> According to LEDE's source code:
>>>> 
>>>> config KERNEL_CRASHLOG
>>>> bool "Crash logging"
>>>> depends on !(arm || powerpc || sparc || TARGET_uml || i386 || x86_64)
>>>> default y
>>>> 
>>>> https://github.com/lede-project/source/blob/master/config/Config-kernel.in
>>>> 
>>>> It is enabled by default on some targets and will be available at
>>>> `/sys/kernel/debug/crashlog` on next boot after crash.
>>>> 
>>>> The implementation detail can be found here:
>>>> https://github.com/lede-project/source/blob/master/target/linux/generic/patches-4.9/930-crashlog.patch
>>>> 
>>>> 
>>>> Best Regards,
>>>> Syrone Wong
>>>> 
>>>> 
>>>> On Thu, Feb 23, 2017 at 10:05 AM, Philip Prindeville
>>>> <philipp_subx at redfish-solutions.com> wrote:
>>>>> Hi,
>>>>> 
>>>>> Has anyone managed to use kdump with OpenWRT/LEDE?
>>>>> 
>>>>> I have a box which periodically panics, and since /var is a link to /tmp/ there are no persistent logs.  Which reminds me: is it safe to configure a third partition on my CF card, format it as ext3, and mount that as /var/log in /etc/fstab?
>>>>> 
>>>>> And how would I modify the build process if I wanted to add additional partitions?
>>>>> 
>>>>> Thanks,
>>>>> 
>>>>> -Philip
>>>>> _______________________________________________
>>>>> openwrt-devel mailing list
>>>>> openwrt-devel at lists.openwrt.org
>>>>> https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel
>>> 
>>> 
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>>