diff options
authorOliver O'Halloran <oohall@gmail.com>2019-01-31 12:53:47 +1100
committerMichael Ellerman <mpe@ellerman.id.au>2019-02-01 10:13:51 +1100
commit5a3840a470c41ec0b85cd36ca80370330656b163 (patch)
parent579b9239c1f38665b21e8d0e6ee83ecc96dbd6bb (diff)
powerpc/papr_scm: Use the correct bind address
When binding an SCM volume to a physical address the hypervisor has the option to return early with a continue token with the expectation that the guest will resume the bind operation until it completes. A quirk of this interface is that the bind address will only be returned by the first bind h-call and the subsequent calls will return 0xFFFF_FFFF_FFFF_FFFF for the bind address. We currently do not save the address returned by the first h-call. As a result we will use the junk address as the base of the bound region if the hypervisor decides to split the bind across multiple h-calls. This bug was found when testing with very large SCM volumes where the bind process would take more time than they hypervisor's internal h-call time limit would allow. This patch fixes the issue by saving the bind address from the first call. Cc: stable@vger.kernel.org Fixes: b5beae5e224f ("powerpc/pseries: Add driver for PAPR SCM regions") Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c
index 7d6457ab5d34..bba281b1fe1b 100644
--- a/arch/powerpc/platforms/pseries/papr_scm.c
+++ b/arch/powerpc/platforms/pseries/papr_scm.c
@@ -43,6 +43,7 @@ static int drc_pmem_bind(struct papr_scm_priv *p)
unsigned long ret[PLPAR_HCALL_BUFSIZE];
uint64_t rc, token;
+ uint64_t saved = 0;
* When the hypervisor cannot map all the requested memory in a single
@@ -56,6 +57,8 @@ static int drc_pmem_bind(struct papr_scm_priv *p)
rc = plpar_hcall(H_SCM_BIND_MEM, ret, p->drc_index, 0,
p->blocks, BIND_ANY_ADDR, token);
token = ret[0];
+ if (!saved)
+ saved = ret[1];
} while (rc == H_BUSY);
@@ -64,7 +67,7 @@ static int drc_pmem_bind(struct papr_scm_priv *p)
return -ENXIO;
- p->bound_addr = ret[1];
+ p->bound_addr = saved;
dev_dbg(&p->pdev->dev, "bound drc %x to %pR\n", p->drc_index, &p->res);