diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2018-04-10 21:49:33 +1000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-24 09:32:07 +0200 |
| commit | dace93d0f8d00412a1d13848a7958c9c7a634289 (patch) | |
| tree | e3accf69484953f51ef8820980c71e81a69f54ee /arch | |
| parent | 16d770bd91fc1c9659639adb2bd4c614934fc9be (diff) | |
powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops
commit 3b8070335f751aac9f1526ae2e012e6f5b8b0f21 upstream.
The OPAL NVRAM driver does not sleep in case it gets OPAL_BUSY or
OPAL_BUSY_EVENT from firmware, which causes large scheduling
latencies, and various lockup errors to trigger (again, BMC reboot
can cause it).
Fix this by converting it to the standard form OPAL_BUSY loop that
sleeps.
Fixes: 628daa8d5abf ("powerpc/powernv: Add RTC and NVRAM support plus RTAS fallbacks")
Depends-on: 34dd25de9fe3 ("powerpc/powernv: define a standard delay for OPAL_BUSY type retry loops")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/platforms/powernv/opal-nvram.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/powerpc/platforms/powernv/opal-nvram.c b/arch/powerpc/platforms/powernv/opal-nvram.c index ba2ff06a2c98..1bceb95f422d 100644 --- a/arch/powerpc/platforms/powernv/opal-nvram.c +++ b/arch/powerpc/platforms/powernv/opal-nvram.c @@ -11,6 +11,7 @@ #define DEBUG +#include <linux/delay.h> #include <linux/kernel.h> #include <linux/init.h> #include <linux/of.h> @@ -56,8 +57,12 @@ static ssize_t opal_nvram_write(char *buf, size_t count, loff_t *index) while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { rc = opal_write_nvram(__pa(buf), count, off); - if (rc == OPAL_BUSY_EVENT) + if (rc == OPAL_BUSY_EVENT) { + msleep(OPAL_BUSY_DELAY_MS); opal_poll_events(NULL); + } else if (rc == OPAL_BUSY) { + msleep(OPAL_BUSY_DELAY_MS); + } } if (rc) |