[PATCH v2 1/3] spapr: Disable ibm, pa-features HTM bit

Sam Bobroff sam.bobroff at au1.ibm.com
Wed Jul 6 15:35:21 AEST 2016

There are a few issues with our handling of the ibm,pa-features
HTM bit:

- We don't support transactional memory in PR KVM, so don't tell
  the OS that we do.

- In full emulation we have a minimal implementation of HTM that always
  fails, so for performance reasons lets not tell the OS that we
  support it either.

- In HV KVM mode, we should mirror the host HTM enabled state by
  checking a KVM capability or looking at the AT_HWCAP2 bit.

For now unconditionally disable it by removing HTM from the
pa-features bits.  It will be re-enabled in a subsequent patch
specifically for HV KVM.

Signed-off-by: Sam Bobroff <sam.bobroff at au1.ibm.com>
 hw/ppc/spapr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 78ebd9e..704aae7 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -635,7 +635,7 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset,
         0xf6, 0x1f, 0xc7, 0xc0, 0x80, 0xf0,
         0x80, 0x00, 0x00, 0x00, 0x00, 0x00,
         0x00, 0x00, 0x00, 0x00, 0x80, 0x00,
-        0x80, 0x00, 0x80, 0x00, 0x80, 0x00 };
+        0x80, 0x00, 0x80, 0x00, 0x00, 0x00 };
     uint8_t *pa_features;
     size_t pa_size;

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