[PATCH v2 7/7] platform/x86/amd/hsmp: Drop stale metric table mapping on rebind

[Muralidhara M K]

Now that the ACPI socket array persists across a non-final unbind, a
stale metric_tbl_addr from a previous bind can still be recorded in the
socket when hsmp_get_tbl_dram_base() runs on a later (re)probe.
Re-ioremap()ing over it leaks one metric-table mapping per unbind/rebind
cycle.

iounmap() any existing mapping before remapping.  This runs during
(re)probe before the metric sysfs attribute is exposed, so no reader can
be using the old mapping.

Signed-off-by: Muralidhara M K <muralidhara.mk@xxxxxxx>
---
 drivers/platform/x86/amd/hsmp/hsmp.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/platform/x86/amd/hsmp/hsmp.c b/drivers/platform/x86/amd/hsmp/hsmp.c
index 2e836124f486..a75190ea41c4 100644
--- a/drivers/platform/x86/amd/hsmp/hsmp.c
+++ b/drivers/platform/x86/amd/hsmp/hsmp.c
@@ -498,6 +498,17 @@ int hsmp_get_tbl_dram_base(u16 sock_ind)
 		dev_err(sock->dev, "Invalid DRAM address for metric table\n");
 		return -ENOMEM;
 	}
+	/*
+	 * The ACPI socket array now persists across a non-final unbind, so a
+	 * stale mapping from a previous bind can still be recorded here.  Drop
+	 * it before remapping to avoid leaking one metric-table mapping per
+	 * unbind/rebind cycle.  This runs during (re)probe before the metric
+	 * sysfs attribute is exposed, so no reader can be using it.
+	 */
+	if (sock->metric_tbl_addr) {
+		iounmap(sock->metric_tbl_addr);
+		sock->metric_tbl_addr = NULL;
+	}
 	sock->metric_tbl_addr = ioremap(dram_addr, sizeof(struct hsmp_metric_table));
 	if (!sock->metric_tbl_addr) {
 		dev_err(sock->dev, "Failed to ioremap metric table addr\n");
-- 
2.43.0