[lkml]   [2014]   [Feb]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [perf tool] record failure with 3.14-rc4
On Mon, Feb 24, 2014 at 05:24:41PM +0000, Will Deacon wrote:
> Hi guys,
> If I try to run perf record as a non-root user, I end up with the following
> (unhelpful) error:
> $ perf record -e cycles ls
> [...]
> Not enough memory for reading perf file header
> This is because the addresses in /proc/kallsyms always read as 0x0 when
> viewed by a non-privileged user, causing kallsyms__get_function_start to
> return 0x0 in args.start. machine__create_kernel_maps then treats this as
> an error an returns -1 to perf_session__create_kernel_maps, causing
> perf_session__new to fail and perf to exit.
> The perf tool code in 3.13 is perfectly happy creating maps at 0x0, but I
> can see this has changed quite substantially in the recent merge window.
> Any ideas? We could fix kallsyms__get_function_start to return < 0 on
> failure then fix the checks in the callers. Adrian?
not sure it's related, but i sent out rfc some time ago
for similar bad error messages:

maybe it could be updated for your case as well,
I'll try to check deeply later


 \ /
  Last update: 2014-02-25 23:42    [W:0.031 / U:2.508 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site