kernel/arch/openrisc/include/asm/barrier.h, branch linux-rolling-stableHosts the 0x221E linux distro kernel.https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-rolling-stable2026-03-04T12:20:18Zopenrisc: define arch-specific version of nop()2026-03-04T12:20:18ZBrian Masneybmasney@redhat.com2026-01-20T17:07:23Zurn:sha1:a729596086984e76cba5e8f7fe52e912c08a24ae
[ Upstream commit 0dfffa5479d6260d04d021f69203b1926f73d889 ]
When compiling a driver written for MIPS on OpenRISC that uses the nop()
function, it fails due to the following error:
drivers/watchdog/pic32-wdt.c: Assembler messages:
drivers/watchdog/pic32-wdt.c:125: Error: unrecognized instruction `nop'
The driver currently uses the generic version of nop() from
include/asm-generic/barrier.h:
#ifndef nop
#define nop() asm volatile ("nop")
#endif
Let's fix this on OpenRISC by defining an architecture-specific version
of nop().
This was tested by performing an allmodconfig openrisc cross compile on
an aarch64 host.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202601180236.BVy480We-lkp@intel.com/
Signed-off-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
openrisc: Define memory barrier mb2021-05-15T07:00:10ZPeter Zijlstrapeterz@infradead.org2021-04-14T12:45:43Zurn:sha1:8b549c18ae81dbc36fb11e4aa08b8378c599ca95
This came up in the discussion of the requirements of qspinlock on an
architecture. OpenRISC uses qspinlock, but it was noticed that the
memmory barrier was not defined.
Peter defined it in the mail thread writing:
As near as I can tell this should do. The arch spec only lists
this one instruction and the text makes it sound like a completion
barrier.
This is correct so applying this patch.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
[shorne@gmail.com:Turned the mail into a patch]
Signed-off-by: Stafford Horne <shorne@gmail.com>