RE: [PATCH] ACPICA: Events: Execute some _REG methods in early boot

From: Zheng, Lv
Date: Mon Mar 07 2016 - 01:36:57 EST


Hi,

First of all, why don't you respond on the kernel bugzilla?
Posting a fix here directly without communication doesn't look like a constructive help but more like a destructive attack to me.

> From: linux-acpi-owner@xxxxxxxxxxxxxxx [mailto:linux-acpi-
> Subject: [PATCH] ACPICA: Events: Execute some _REG methods in early boot
>
> The regression caused _REG methods to not be run in early boot for all
> space IDs, but a removed comment stated that _REG methods should be
> executed for IDs like embedded_controller. Before the regression this
> was the case:
>
> [ 0.230469] Executing Method \_SB.PCI0.LPCB.EC._REG
> [ 0.230531] Initializing Region \GNVS
> [ 0.230607] Initializing Region \_SB.PCI0.LPCB.EC.ECOR
> [ 0.231043] Initializing Region \_SB.PCI0.IGPU.IGDM
[Lv Zheng]
As I said in the previous reply, this is the known issue and can be fixed by applying the whole series.
Especially this commit:
https://patchwork.kernel.org/patch/8241421/
That's why I asked you to test again by applying the whole series.
And that's why after having not seen your response for so long time, we prepared a test branch and was waiting for your response.

You need to post acpidump there to have the issue root caused so that more accurate fix can be generated.

>
> After the regression the initialisation is not done and ODEBUG warnings
> are shown at boot and/or shutdown:
>
> [ 6.676570] WARNING: CPU: 0 PID: 3317 at lib/debugobjects.c:263
> debug_print_object+0x85/0xa0()
> [ 6.676576] ODEBUG: assert_init not available (active state 0) object type:
> timer_list hint: stub_timer+0x0/0x20
> [ 6.676578] Modules linked in:
> [ 6.676582] CPU: 0 PID: 3317 Comm: ccpd Not tainted 4.5.0-rc6 #509
> [ 6.676584] Hardware name: Apple Inc. MacBookPro10,2/Mac-
> AFD8A9D944EA4843, BIOS MBP102.88Z.0106.B0A.1509130955 09/13/2015
> [ 6.676586] 0000000000000000 ffff880256543db0 ffffffff814802b5
> ffff880256543df8
> [ 6.676590] ffffffff81f40dbd ffff880256543de8 ffffffff810bd0ec
> ffff880256543e90
> [ 6.676594] ffffffff822532c0 ffffffff81f40e63 ffffffff83138c88
> 0000000001fdf040
> [ 6.676598] Call Trace:
> [ 6.676603] [<ffffffff814802b5>] dump_stack+0x67/0x92
> [ 6.676608] [<ffffffff810bd0ec>] warn_slowpath_common+0x7c/0xb0
> [ 6.676611] [<ffffffff810bd167>] warn_slowpath_fmt+0x47/0x50
> [ 6.676614] [<ffffffff8149d7a5>] debug_print_object+0x85/0xa0
> [ 6.676616] [<ffffffff8111f440>] ? cascade+0x70/0x70
> [ 6.676620] [<ffffffff8149e398>] debug_object_assert_init+0xf8/0x130
> [ 6.676624] [<ffffffff811038cd>] ? trace_hardirqs_on+0xd/0x10
> [ 6.676626] [<ffffffff8111fcff>] del_timer+0x1f/0x70
> [ 6.676631] [<ffffffff811852f1>] laptop_sync_completion+0x61/0x100
> [ 6.676633] [<ffffffff81185290>] ? laptop_io_completion+0x30/0x30
> [ 6.676637] [<ffffffff81212c9f>] sys_sync+0x7f/0x90
> [ 6.676641] [<ffffffff81ad0d97>] entry_SYSCALL_64_fastpath+0x12/0x6f
>
> Fixes: efaed9be998b ("ACPICA: Events: Enhance acpi_ev_execute_reg_method()
> to ensure no _REG evaluations can happen during OS early boot stages")
> Link: https://lkml.org/lkml/2016/2/3/273
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112911
> Signed-off-by: Chris Bainbridge <chris.bainbridge@xxxxxxxxx>
> ---
> drivers/acpi/acpica/evregion.c | 22 +++++++++++++++++++++-
> 1 file changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/acpica/evregion.c b/drivers/acpi/acpica/evregion.c
> index 47092b4d633c..d0b02ef0effa 100644
> --- a/drivers/acpi/acpica/evregion.c
> +++ b/drivers/acpi/acpica/evregion.c
> @@ -590,6 +590,7 @@ acpi_ev_execute_reg_method(union
> acpi_operand_object *region_obj, u32 function)
> union acpi_operand_object *args[3];
> union acpi_operand_object *region_obj2;
> acpi_status status;
> + bool sp;
>
> ACPI_FUNCTION_TRACE(ev_execute_reg_method);
>
> @@ -598,9 +599,28 @@ acpi_ev_execute_reg_method(union
> acpi_operand_object *region_obj, u32 function)
> return_ACPI_STATUS(AE_NOT_EXIST);
> }
>
> + /*
> + * For the default space_IDs, (the IDs for which there are default region
> handlers
> + * installed) Only execute the _REG methods if the global initialization
> _REG
> + * methods have already been run (via acpi_initialize_objects). In other
> words,
> + * we will defer the execution of the _REG methods for these
> space_IDs until
> + * execution of acpi_initialize_objects. This is done because we need
> the handlers
> + * for the default spaces (mem/io/pci/table) to be installed before we
> can run
> + * any control methods (or _REG methods). There is known BIOS code
> that depends
> + * on this.
> + *
> + * For all other space_IDs, we can safely execute the _REG methods
> immediately.
> + * This means that for IDs like embedded_controller, this function
> should be called
> + * only after acpi_enable_subsystem has been called.
> + */
> +
> + sp = (region_obj->region.space_id ==
> ACPI_ADR_SPACE_SYSTEM_MEMORY ||
> + region_obj->region.space_id == ACPI_ADR_SPACE_SYSTEM_IO ||
> + region_obj->region.space_id == ACPI_ADR_SPACE_PCI_CONFIG ||
> + region_obj->region.space_id == ACPI_ADR_SPACE_DATA_TABLE);
> if (region_obj2->extra.method_REG == NULL ||
> region_obj->region.handler == NULL ||
> - !acpi_gbl_reg_methods_enabled) {
> + (sp && !acpi_gbl_reg_methods_enabled)) {
> return_ACPI_STATUS(AE_OK);
> }
>
[Lv Zheng]
The above fix looks hackish to me.
IMO, if you want to stop regressions that are triggered by this commit.
A simpler and proper way would be to move acpi_gbl_reg_method_enabled = TRUE to the end of acpi_load_tables().
So that when the order of table loading and ECDT probing is corrected, the correct logic can still apply.

I don't have ECDT platforms in hand to confirm.
Can you help to just give it a try?

Thanks and best regards
-Lv

> --
> 2.1.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html