On 22:22-20150123, Kirill A. Shutemov wrote:

On Fri, Jan 23, 2015 at 12:37:06PM -0600, Nishanth Menon wrote:

quoted

On 09:39-20150123, Tyler Baker wrote:

quoted

Hi,

On 23 January 2015 at 09:27, Nishanth Menon [off-list ref] wrote:

quoted

On 16:05-20150120, Kirill A. Shutemov wrote:
[..]

quoted

Signed-off-by: Kirill A. Shutemov <redacted>
Reported-by: Nishanth Menon <nm@ti.com>

Just to close on this thread:
https://github.com/nmenon/kernel-test-logs/tree/next-20150123 looks good
and back to old status. Thank you folks for all the help.

I just reviewed the boot logs for next-20150123 and there still seems
to be a related issue. I've been boot testing
multi_v7_defconfig+CONFIG_ARM_LPAE=y kernel configurations which still
seem broken.

For example here are two boots with exynos5250-arndale, one with
multi_v7_defconfig+CONFIG_ARM_LPAE=y [1] and the other with
multi_v7_defconfig[2]. You can see the kernel configurations with
CONFIG_ARM_LPAE=y show the splat:

[   14.605950] ------------[ cut here ]------------
[   14.609163] WARNING: CPU: 1 PID: 63 at ../mm/mmap.c:2858
exit_mmap+0x1b8/0x224()
[   14.616548] Modules linked in:
[   14.619553] CPU: 1 PID: 63 Comm: init Not tainted 3.19.0-rc5-next-20150123 #1
[   14.626713] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[   14.632830] [] (unwind_backtrace) from [] (show_stack+0x10/0x14)
[   14.640473] [] (show_stack) from [] (dump_stack+0x78/0x94)
[   14.647678] [] (dump_stack) from [] (warn_slowpath_common+0x74/0xb0)
[   14.655744] [] (warn_slowpath_common) from [] (warn_slowpath_null+0x1c/0x24)
[   14.664510] [] (warn_slowpath_null) from [] (exit_mmap+0x1b8/0x224)
[   14.672497] [] (exit_mmap) from [] (mmput+0x40/0xf8)
[   14.679180] [] (mmput) from [] (flush_old_exec+0x328/0x604)
[   14.686471] [] (flush_old_exec) from [] (load_elf_binary+0x26c/0x11f4)
[   14.694715] [] (load_elf_binary) from [] (search_binary_handler+0x98/0x244)
[   14.703395] [] (search_binary_handler) from []
(do_execveat_common+0x4dc/0x5bc)
[   14.712421] [] (do_execveat_common) from [] (do_execve+0x28/0x30)
[   14.720235] [] (do_execve) from [] (ret_fast_syscall+0x0/0x34)
[   14.727782] ---[ end trace 5e3ca48b454c7e0a ]---
[   14.733758] ------------[ cut here ]------------

Has anyone else tested with CONFIG_ARM_LPAE=y that can confirm my findings?

Uggh... I missed since i was looking at non LPAE omap2plus_defconfig.

Dual A15 OMAP5432 with multi_v7_defconfig + CONFIG_ARM_LPAE=y
https://github.com/nmenon/kernel-test-logs/blob/next-20150123/multi_lpae_defconfig/omap5-evm.txt

Dual A15 DRA7/AM572x with same configuration as above.
https://raw.githubusercontent.com/nmenon/kernel-test-logs/next-20150123/multi_lpae_defconfig/dra7xx-evm.txt
https://github.com/nmenon/kernel-test-logs/blob/next-20150123/multi_lpae_defconfig/am57xx-evm.txt

Single A15 DRA72 with same configuration as above:
https://raw.githubusercontent.com/nmenon/kernel-test-logs/next-20150123/multi_lpae_defconfig/dra72x-evm.txt

You are right. the issue re-appears with LPAE on :(
Apologies on missing that.

Guys, could you instrument mm_{inc,dec}_nr_pmds() with dump_stack() +
printk() of the counter and add printk() on mmap_exit() then run a simple
program which triggers the issue?

The simplest program I think we are all running is "boot to shell" - I
mean, have'nt spend more time digging at it as I am not in a familiar
territory here. :( is there any instrumentation patch you want us to try?

-- 
Regards,
Nishanth Menon