drm/i915: avoid big kmallocs on reading error state
Sometimes when user is trying to get error state out from
debugfs after gpu hang, the memory is low and/or fragmented
enough that kmalloc in seq_file will fail.
Prevent big kmalloc by avoiding seq_file and instead convert
error state to string in smaller chunks.
v2: better alloc flags, better truncate, correct
locking, and error handling improvements (Chris Wilson)
v3: printf annotations (Daniel Vetter)
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
index 67a2501..836794b 100644
--- a/drivers/gpu/drm/i915/intel_overlay.c
+++ b/drivers/gpu/drm/i915/intel_overlay.c
@@ -1485,14 +1485,15 @@
}
void
-intel_overlay_print_error_state(struct seq_file *m, struct intel_overlay_error_state *error)
+intel_overlay_print_error_state(struct drm_i915_error_state_buf *m,
+ struct intel_overlay_error_state *error)
{
- seq_printf(m, "Overlay, status: 0x%08x, interrupt: 0x%08x\n",
- error->dovsta, error->isr);
- seq_printf(m, " Register file at 0x%08lx:\n",
- error->base);
+ i915_error_printf(m, "Overlay, status: 0x%08x, interrupt: 0x%08x\n",
+ error->dovsta, error->isr);
+ i915_error_printf(m, " Register file at 0x%08lx:\n",
+ error->base);
-#define P(x) seq_printf(m, " " #x ": 0x%08x\n", error->regs.x)
+#define P(x) i915_error_printf(m, " " #x ": 0x%08x\n", error->regs.x)
P(OBUF_0Y);
P(OBUF_1Y);
P(OBUF_0U);