4.4-stable review patch. If anyone has any objections, please let me know.
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From: Edgar Cherkasov echerkasov@dev.rtsoft.ru
commit 08d9db00fe0e300d6df976e6c294f974988226dd upstream.
The i2c-scmi driver crashes when the SMBus Write Block transaction is executed:
WARNING: CPU: 9 PID: 2194 at mm/page_alloc.c:3931 __alloc_pages_slowpath+0x9db/0xec0 Call Trace: ? get_page_from_freelist+0x49d/0x11f0 ? alloc_pages_current+0x6a/0xe0 ? new_slab+0x499/0x690 __alloc_pages_nodemask+0x265/0x280 alloc_pages_current+0x6a/0xe0 kmalloc_order+0x18/0x40 kmalloc_order_trace+0x24/0xb0 ? acpi_ut_allocate_object_desc_dbg+0x62/0x10c __kmalloc+0x203/0x220 acpi_os_allocate_zeroed+0x34/0x36 acpi_ut_copy_eobject_to_iobject+0x266/0x31e acpi_evaluate_object+0x166/0x3b2 acpi_smbus_cmi_access+0x144/0x530 [i2c_scmi] i2c_smbus_xfer+0xda/0x370 i2cdev_ioctl_smbus+0x1bd/0x270 i2cdev_ioctl+0xaa/0x250 do_vfs_ioctl+0xa4/0x600 SyS_ioctl+0x79/0x90 do_syscall_64+0x73/0x130 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 ACPI Error: Evaluating _SBW: 4 (20170831/smbus_cmi-185)
This problem occurs because the length of ACPI Buffer object is not defined/initialized in the code before a corresponding ACPI method is called. The obvious patch below fixes this issue.
Signed-off-by: Edgar Cherkasov echerkasov@dev.rtsoft.ru Acked-by: Viktor Krasnov vkrasnov@dev.rtsoft.ru Acked-by: Michael Brunner Michael.Brunner@kontron.com Signed-off-by: Wolfram Sang wsa@the-dreams.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/i2c/busses/i2c-scmi.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/i2c/busses/i2c-scmi.c +++ b/drivers/i2c/busses/i2c-scmi.c @@ -152,6 +152,7 @@ acpi_smbus_cmi_access(struct i2c_adapter mt_params[3].type = ACPI_TYPE_INTEGER; mt_params[3].integer.value = len; mt_params[4].type = ACPI_TYPE_BUFFER; + mt_params[4].buffer.length = len; mt_params[4].buffer.pointer = data->block + 1; } break;