[PATCH AUTOSEL 4.19 055/209] powerpc/pseries: Fix DTL buffer registration

Sasha Levin
2019-11-13T01:51:46Z

From: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>

[ Upstream commit db787af1b8a6b4be428ee2ea7d409dafcaa4a43c ]

When CONFIG_VIRT_CPU_ACCOUNTING_NATIVE is not set, we register the DTL
buffer for a cpu when the associated file under powerpc/dtl in debugfs
is opened. When doing so, we need to set the size of the buffer being
registered in the second u32 word of the buffer. This needs to be in big
endian, but we are not doing the conversion resulting in the below error
showing up in dmesg:

dtl_start: DTL registration for cpu 0 (hw 0) failed with -4

Fix this in the obvious manner.

Fixes: 7c105b63bd98 ("powerpc: Add CONFIG_CPU_LITTLE_ENDIAN kernel config option.")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/platforms/pseries/dtl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/pseries/dtl.c b/arch/powerpc/platforms/pseries/dtl.c
index 18014cdeb590a..c762689e0eb33 100644
--- a/arch/powerpc/platforms/pseries/dtl.c
+++ b/arch/powerpc/platforms/pseries/dtl.c
@@ -149,7 +149,7 @@ static int dtl_start(struct dtl *dtl)

/* Register our dtl buffer with the hypervisor. The HV expects the
* buffer size to be passed in the second word of the buffer */
- ((u32 *)dtl->buf)[1] = DISPATCH_LOG_BYTES;
+ ((u32 *)dtl->buf)[1] = cpu_to_be32(DISPATCH_LOG_BYTES);

hwcpu = get_hard_smp_processor_id(dtl->cpu);
addr = __pa(dtl->buf);
--
2.20.1