From dabaa4ae32062cb3f3d995e5c63e6cef54ad079b Mon Sep 17 00:00:00 2001 From: Janne Grunau Date: Sat, 23 Nov 2024 22:44:05 +0100 Subject: dm: Add dm_remove_devices_active() for ordered device removal This replaces dm_remove_devices_flags() calls in all boot implementations to ensure non vital devices are consistently removed first. All boot implementation except arch/arm/lib/bootm.c currently just call dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL). This can result in crashes when dependencies between devices exists. The driver model's design document describes DM_FLAG_VITAL as "indicates that the device is 'vital' to the operation of other devices". Device removal at boot should follow this. Instead of adding dm_remove_devices_flags() with (DM_REMOVE_ACTIVE_ALL | DM_REMOVE_NON_VITAL) everywhere add dm_remove_devices_active() which does this. Fixes a NULL pointer deref in the apple dart IOMMU driver during EFI boot. The xhci-pci (driver which depends on the IOMMU to work) removes its mapping on removal. This explodes when the IOMMU device was removed first. dm_remove_devices_flags() is kept since it is used for testing of device_remove() calls in dm. Signed-off-by: Janne Grunau --- test/dm/core.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) (limited to 'test') diff --git a/test/dm/core.c b/test/dm/core.c index 7371d3ff426..c59ffc6f611 100644 --- a/test/dm/core.c +++ b/test/dm/core.c @@ -999,6 +999,56 @@ static int dm_test_remove_vital(struct unit_test_state *uts) } DM_TEST(dm_test_remove_vital, 0); +/* Test removal of 'active' devices */ +static int dm_test_remove_active(struct unit_test_state *uts) +{ + struct udevice *normal, *dma, *vital, *dma_vital; + + /* Skip the behaviour in test_post_probe() */ + uts->skip_post_probe = 1; + + ut_assertok(device_bind_by_name(uts->root, false, &driver_info_manual, + &normal)); + ut_assertnonnull(normal); + + ut_assertok(device_bind_by_name(uts->root, false, &driver_info_act_dma, + &dma)); + ut_assertnonnull(dma); + + ut_assertok(device_bind_by_name(uts->root, false, + &driver_info_vital_clk, &vital)); + ut_assertnonnull(vital); + + ut_assertok(device_bind_by_name(uts->root, false, + &driver_info_act_dma_vital_clk, + &dma_vital)); + ut_assertnonnull(dma_vital); + + /* Probe the devices */ + ut_assertok(device_probe(normal)); + ut_assertok(device_probe(dma)); + ut_assertok(device_probe(vital)); + ut_assertok(device_probe(dma_vital)); + + /* Check that devices are active right now */ + ut_asserteq(true, device_active(normal)); + ut_asserteq(true, device_active(dma)); + ut_asserteq(true, device_active(vital)); + ut_asserteq(true, device_active(dma_vital)); + + /* Remove active devices in an ordered way */ + dm_remove_devices_active(); + + /* Check that all devices are inactive right now */ + ut_asserteq(true, device_active(normal)); + ut_asserteq(false, device_active(dma)); + ut_asserteq(true, device_active(vital)); + ut_asserteq(false, device_active(dma_vital)); + + return 0; +} +DM_TEST(dm_test_remove_active, 0); + static int dm_test_uclass_before_ready(struct unit_test_state *uts) { struct uclass *uc; -- cgit v1.3.1