Re: [PATCH] perf: fix kernel panic when parsing user space CS saved in pt_regs

2014-06-05 Thread Peter Zijlstra
On Thu, Jun 05, 2014 at 09:15:36PM +0800, Zhang, Yanmin wrote: > Sorry for misleading you. It depends on backend. Pstore can use RAM or > other storage, for example, EFI-provided backend. If using EFI backend, > pstore can keep persistent across cold reset or even power outrages. > > If using RAM

Re: [PATCH] perf: fix kernel panic when parsing user space CS saved in pt_regs

2014-06-05 Thread Zhang, Yanmin
On 2014/6/5 17:15, Peter Zijlstra wrote: On Thu, Jun 05, 2014 at 04:00:24PM +0800, Zhang, Yanmin wrote: On 2014/6/5 15:55, Peter Zijlstra wrote: Why does pstore cause corruption? I thought that stuff was supposed to be 'good' ? pstore is good if the board is reset by WarmReset as memory conten

Re: [PATCH] perf: fix kernel panic when parsing user space CS saved in pt_regs

2014-06-05 Thread Peter Zijlstra
On Thu, Jun 05, 2014 at 04:00:24PM +0800, Zhang, Yanmin wrote: > On 2014/6/5 15:55, Peter Zijlstra wrote: > >Why does pstore cause corruption? I thought that stuff was supposed to > >be 'good' ? > pstore is good if the board is reset by WarmReset as memory content is kept > across rebooting. > If

Re: [PATCH] perf: fix kernel panic when parsing user space CS saved in pt_regs

2014-06-05 Thread Zhang, Yanmin
On 2014/6/5 15:55, Peter Zijlstra wrote: On Thu, Jun 05, 2014 at 03:33:21PM +0800, Liu ShuoX wrote: On Thu 5.Jun'14 at 9:19:19 +0200, Peter Zijlstra wrote: On Thu, Jun 05, 2014 at 10:36:10AM +0800, Liu ShuoX wrote: From: Zhang Yanmin We hit a kernel panic when running perf to collect some

Re: [PATCH] perf: fix kernel panic when parsing user space CS saved in pt_regs

2014-06-05 Thread Peter Zijlstra
On Thu, Jun 05, 2014 at 03:33:21PM +0800, Liu ShuoX wrote: > On Thu 5.Jun'14 at 9:19:19 +0200, Peter Zijlstra wrote: > >On Thu, Jun 05, 2014 at 10:36:10AM +0800, Liu ShuoX wrote: > >>From: Zhang Yanmin > >> > >>We hit a kernel panic when running perf to collect some performance data. > >>kenel i

Re: [PATCH] perf: fix kernel panic when parsing user space CS saved in pt_regs

2014-06-05 Thread Liu ShuoX
On Thu 5.Jun'14 at 9:19:19 +0200, Peter Zijlstra wrote: On Thu, Jun 05, 2014 at 10:36:10AM +0800, Liu ShuoX wrote: From: Zhang Yanmin We hit a kernel panic when running perf to collect some performance data. kenel is x86_64 and user space apps are 32bit. [ 71.965351, 1] [ Binder_2]

Re: [PATCH] perf: fix kernel panic when parsing user space CS saved in pt_regs

2014-06-05 Thread Peter Zijlstra
On Thu, Jun 05, 2014 at 10:36:10AM +0800, Liu ShuoX wrote: > From: Zhang Yanmin > > We hit a kernel panic when running perf to collect some performance data. > kenel is x86_64 and user space apps are 32bit. > > [ 71.965351, 1] [ Binder_2] BUG: unable to handle kernel NULL pointer > dere

[PATCH] perf: fix kernel panic when parsing user space CS saved in pt_regs

2014-06-04 Thread Liu ShuoX
From: Zhang Yanmin We hit a kernel panic when running perf to collect some performance data. kenel is x86_64 and user space apps are 32bit. [ 71.965351, 1] [ Binder_2] BUG: unable to handle kernel NULL pointer dereference at 0004 [ 71.965360, 1] [ Binder_2] IP: []