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| author |   Nicholas Piggin <npiggin@gmail.com> | 2018-04-01 20:36:15 +1000 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2018-04-03 22:59:57 +1000 |
| commit | f2748bdfe157343eb8cf910a1d89ccf2fd20100b (patch) | |
| tree | 5088070ac7b1f8e47f168ecfd275f821c322e422 /arch/powerpc/platforms/powernv/setup.c | |
| parent | powerpc: hard disable irqs in smp_send_stop loop (diff) | |
| download | linux-dev-f2748bdfe157343eb8cf910a1d89ccf2fd20100b.tar.xz linux-dev-f2748bdfe157343eb8cf910a1d89ccf2fd20100b.zip | |
powerpc/powernv: Always stop secondaries before reboot/shutdown
Currently powernv reboot and shutdown requests just leave secondaries
to do their own things. This is undesirable because they can trigger
any number of watchdogs while waiting for reboot, but also we don't
know what else they might be doing -- they might be causing trouble,
trampling memory, etc.
The opal scheduled flash update code already ran into watchdog problems
due to flashing taking a long time, and it was fixed with 2196c6f1ed
("powerpc/powernv: Return secondary CPUs to firmware before FW update"),
which returns secondaries to opal. It's been found that regular reboots
can take over 10 seconds, which can result in the hard lockup watchdog
firing,
reboot: Restarting system
[ 360.038896709,5] OPAL: Reboot request...
Watchdog CPU:0 Hard LOCKUP
Watchdog CPU:44 detected Hard LOCKUP other CPUS:16
Watchdog CPU:16 Hard LOCKUP
watchdog: BUG: soft lockup - CPU#16 stuck for 3s! [swapper/16:0]
This patch removes the special case for flash update, and calls
smp_send_stop in all cases before calling reboot/shutdown.
smp_send_stop could return CPUs to OPAL, the main reason not to is
that the request could come from a NMI that interrupts OPAL code,
so re-entry to OPAL can cause a number of problems. Putting
secondaries into simple spin loops improves the chances of a
successful reboot.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/platforms/powernv/setup.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/setup.c | 15 |
1 files changed, 5 insertions, 10 deletions
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c index 5f963286232f..ef8c9ce53a61 100644 --- a/arch/powerpc/platforms/powernv/setup.c +++ b/arch/powerpc/platforms/powernv/setup.c @@ -201,17 +201,12 @@ static void pnv_prepare_going_down(void) */ opal_event_shutdown(); - /* Soft disable interrupts */ - local_irq_disable(); + /* Print flash update message if one is scheduled. */ + opal_flash_update_print_message(); - /* - * Return secondary CPUs to firwmare if a flash update - * is pending otherwise we will get all sort of error - * messages about CPU being stuck etc.. This will also - * have the side effect of hard disabling interrupts so - * past this point, the kernel is effectively dead. - */ - opal_flash_term_callback(); + smp_send_stop(); + + hard_irq_disable(); } static void __noreturn pnv_restart(char *cmd) |