From: Haren Myneni haren@linux.ibm.com
[ Upstream commit f3e5d9e53e74d77e711a2c90a91a8b0836a9e0b3 ]
Generally the hypervisor decides to allocate a window on different VAS instances. But if user space wishes to allocate on the current VAS instance where the process is executing, the kernel has to pass associativity domain IDs to allocate VAS window HCALL.
To determine the associativity domain IDs for the current CPU, smp_processor_id() is passed to node associativity HCALL which may return H_P2 (-55) error during DLPAR CPU event. This is because Linux CPU numbers (smp_processor_id()) are not the same as the hypervisor's view of CPU numbers.
Fix the issue by passing hard_smp_processor_id() with VPHN_FLAG_VCPU flag (PAPR 14.11.6.1 H_HOME_NODE_ASSOCIATIVITY).
Fixes: b22f2d88e435 ("powerpc/pseries/vas: Integrate API with open/close windows") Reviewed-by: Nathan Lynch nathanl@linux.ibm.com Signed-off-by: Haren Myneni haren@linux.ibm.com [mpe: Update change log to mention Linux vs HV CPU numbers] Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/55380253ea0c11341824cd4c0fc6bbcfc5752689.camel@lin... Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/platforms/pseries/vas.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/platforms/pseries/vas.c b/arch/powerpc/platforms/pseries/vas.c index 7e6e6dd2e33e..1a2cbc156e8f 100644 --- a/arch/powerpc/platforms/pseries/vas.c +++ b/arch/powerpc/platforms/pseries/vas.c @@ -333,7 +333,7 @@ static struct vas_window *vas_allocate_window(int vas_id, u64 flags, * So no unpacking needs to be done. */ rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, domain, - VPHN_FLAG_VCPU, smp_processor_id()); + VPHN_FLAG_VCPU, hard_smp_processor_id()); if (rc != H_SUCCESS) { pr_err("H_HOME_NODE_ASSOCIATIVITY error: %d\n", rc); goto out;