On 5/30/2018 8:51 PM, Deucher, Alexander wrote: >> -----Original Message----- >> From: amd-gfx [mailto:amd-gfx-bounces at lists.freedesktop.org] On Behalf >> Of Shirish S >> Sent: Wednesday, May 30, 2018 6:19 AM >> To: amd-gfx at lists.freedesktop.org; Wentland, Harry >> <Harry.Wentland at amd.com>; Zhu, Rex <Rex.Zhu at amd.com> >> Cc: S, Shirish <Shirish.S at amd.com> >> Subject: [PATCH] drm/amdgpu: avoid sleep while executing atombios table >> >> This patch replaces kzalloc's flag from GFP_KERNEL to GFP_ATOMIC to avoid >> sleeping in atomic context. >> >> Signed-off-by: Shirish S <shirish.s at amd.com> > Does this actually fix a bug or is it just to be safe. Do actually call atom command tables in an atomic context? I have re-spun V2 patch, with the stack trace so that you can see the path taken. For reference below is the trace: BUG: sleeping function called from invalid context at mm/slab.h:419 in_atomic(): 1, irqs_disabled(): 0, pid: 1137, name: DrmThread CPU: 1 PID: 1137 Comm: DrmThread Tainted: G       W      4.14.43 #10 Call Trace:  dump_stack+0x4d/0x63  ___might_sleep+0x11f/0x12e  __kmalloc+0x76/0x126  amdgpu_atom_execute_table_locked+0xfc/0x285  amdgpu_atom_execute_table+0x5d/0x72  transmitter_control_v1_5+0xef/0x11a  hwss_edp_backlight_control+0x132/0x151  dce110_disable_stream+0x133/0x16e  core_link_disable_stream+0x1c5/0x23b  dce110_reset_hw_ctx_wrap+0xb4/0x1aa  dce110_apply_ctx_to_hw+0x4e/0x6da  ? generic_reg_get+0x1f/0x33  dc_commit_state+0x33f/0x3d2  amdgpu_dm_atomic_commit_tail+0x2cf/0x5d2  ? wait_for_common+0x5b/0x69  commit_tail+0x42/0x64  drm_atomic_helper_commit+0xdc/0xf9  drm_atomic_helper_set_config+0x5c/0x76  __drm_mode_set_config_internal+0x64/0x105 I see it on Stoney when the system's display turns off while entering idle-suspend. Its caused when a BUG hit in the kernel. Thanks & Regards, Shirish S > Alex > >> --- >> drivers/gpu/drm/amd/amdgpu/atom.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/amd/amdgpu/atom.c >> b/drivers/gpu/drm/amd/amdgpu/atom.c >> index bfd98f0..da4558c 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/atom.c >> +++ b/drivers/gpu/drm/amd/amdgpu/atom.c >> @@ -1221,7 +1221,7 @@ static int >> amdgpu_atom_execute_table_locked(struct atom_context *ctx, int index, >> ectx.abort = false; >> ectx.last_jump = 0; >> if (ws) >> - ectx.ws = kzalloc(4 * ws, GFP_KERNEL); >> + ectx.ws = kzalloc(4 * ws, GFP_ATOMIC); >> else >> ectx.ws = NULL; >> >> -- >> 2.7.4 >> >> _______________________________________________ >> amd-gfx mailing list >> amd-gfx at lists.freedesktop.org >> https://lists.freedesktop.org/mailman/listinfo/amd-gfx -- Regards, Shirish S
