In drivers/gpu/drm/amd/amdgpu/amdgpu_ih.c, amdgpu_ih_process calls DRM_DEBUG which calls drm_dbg and finally calls printk. As amdgpu_ih_process is called from an interrupt handler, and interrupt handler should be short as possible.
As printk may lead to bogging down the system or can even create a live lock. printk should not be used in IRQ context. Instead, trace_printk is recommended. Link: https://lwn.net/Articles/365835 Signed-off-by: Fuqian Huang <huangfq.dax...@gmail.com> --- drivers/gpu/drm/drm_print.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c index a17c8a14dba4..90cded140146 100644 --- a/drivers/gpu/drm/drm_print.c +++ b/drivers/gpu/drm/drm_print.c @@ -236,7 +236,7 @@ void drm_dbg(unsigned int category, const char *format, ...) vaf.fmt = format; vaf.va = &args; - printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV", + trace_printk(KERN_DEBUG "[" DRM_NAME ":%ps] %pV", __builtin_return_address(0), &vaf); va_end(args); -- 2.11.0
