4.11-stable review patch. If anyone has any objections, please let me know.
------------------ From: Dan Williams <[email protected]> commit 0de0e198bc7191a0e46cf71f66fec4d07ca91396 upstream. Reading an ACPI table through the /sys/firmware/acpi/tables interface more than 65,536 times leads to the following log message: ACPI Error: Table ffff88033595eaa8, Validation count is zero after increment (20170119/tbutils-423) ...and the table being unavailable until the next reboot. Add the missing acpi_put_table() so the table ->validation_count is decremented after each read. Reported-by: Anush Seetharaman <[email protected]> Fixes: 174cc7187e6f "ACPICA: Tables: Back port acpi_get_table_with_size() ..." Signed-off-by: Dan Williams <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/acpi/sysfs.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -333,14 +333,17 @@ static ssize_t acpi_table_show(struct fi container_of(bin_attr, struct acpi_table_attr, attr); struct acpi_table_header *table_header = NULL; acpi_status status; + ssize_t rc; status = acpi_get_table(table_attr->name, table_attr->instance, &table_header); if (ACPI_FAILURE(status)) return -ENODEV; - return memory_read_from_buffer(buf, count, &offset, - table_header, table_header->length); + rc = memory_read_from_buffer(buf, count, &offset, table_header, + table_header->length); + acpi_put_table(table_header); + return rc; } static int acpi_table_attr_init(struct kobject *tables_obj,
