blob: 6d4aec397ad29f8b66b97360f6345bab732299a3 [file] [log] [blame]
From a41d52f08034e78e3ba036142d6ded37577f6158 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Sat, 29 Jun 2013 23:26:50 +0100
Subject: drm/i915: Break up the large vsnprintf() in print_error_buffers()
So it appears that I have encountered some bogosity when trying to call
i915_error_printf() with many arguments from print_error_buffers(). The
symptom is that the vsnprintf parser tries to interpret an integer arg
as a character string, the resulting OOPS indicating stack corruption.
Replacing the single call with its 13 format specifiers and arguments
with multiple calls to i915_error_printf() worked fine. This patch goes
one step further and introduced i915_error_puts() to pass the strings
simply.
It may not fix the root cause, but it does prevent my box from dying and
I think helps make print_error_buffers() more friendly.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66077
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit baf27f9b17bf2f369f3865e38c41d2163e8d815d)
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
---
drivers/gpu/drm/i915/i915_debugfs.c | 109 ++++++++++++++++++++++++++----------
1 file changed, 79 insertions(+), 30 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 04cf6c09710a..47d6c748057e 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -647,41 +647,44 @@ static const char *purgeable_flag(int purgeable)
return purgeable ? " purgeable" : "";
}
-static void i915_error_vprintf(struct drm_i915_error_state_buf *e,
- const char *f, va_list args)
+static bool __i915_error_ok(struct drm_i915_error_state_buf *e)
{
- unsigned len;
if (!e->err && WARN(e->bytes > (e->size - 1), "overflow")) {
e->err = -ENOSPC;
- return;
+ return false;
}
if (e->bytes == e->size - 1 || e->err)
- return;
+ return false;
- /* Seek the first printf which is hits start position */
- if (e->pos < e->start) {
- len = vsnprintf(NULL, 0, f, args);
- if (e->pos + len <= e->start) {
- e->pos += len;
- return;
- }
+ return true;
+}
- /* First vsnprintf needs to fit in full for memmove*/
- if (len >= e->size) {
- e->err = -EIO;
- return;
- }
+static bool __i915_error_seek(struct drm_i915_error_state_buf *e,
+ unsigned len)
+{
+ if (e->pos + len <= e->start) {
+ e->pos += len;
+ return false;
}
- len = vsnprintf(e->buf + e->bytes, e->size - e->bytes, f, args);
- if (len >= e->size - e->bytes)
- len = e->size - e->bytes - 1;
+ /* First vsnprintf needs to fit in its entirety for memmove */
+ if (len >= e->size) {
+ e->err = -EIO;
+ return false;
+ }
+ return true;
+}
+
+static void __i915_error_advance(struct drm_i915_error_state_buf *e,
+ unsigned len)
+{
/* If this is first printf in this window, adjust it so that
* start position matches start of the buffer
*/
+
if (e->pos < e->start) {
const size_t off = e->start - e->pos;
@@ -701,6 +704,51 @@ static void i915_error_vprintf(struct drm_i915_error_state_buf *e,
e->pos += len;
}
+static void i915_error_vprintf(struct drm_i915_error_state_buf *e,
+ const char *f, va_list args)
+{
+ unsigned len;
+
+ if (!__i915_error_ok(e))
+ return;
+
+ /* Seek the first printf which is hits start position */
+ if (e->pos < e->start) {
+ len = vsnprintf(NULL, 0, f, args);
+ if (!__i915_error_seek(e, len))
+ return;
+ }
+
+ len = vsnprintf(e->buf + e->bytes, e->size - e->bytes, f, args);
+ if (len >= e->size - e->bytes)
+ len = e->size - e->bytes - 1;
+
+ __i915_error_advance(e, len);
+}
+
+static void i915_error_puts(struct drm_i915_error_state_buf *e,
+ const char *str)
+{
+ unsigned len;
+
+ if (!__i915_error_ok(e))
+ return;
+
+ len = strlen(str);
+
+ /* Seek the first printf which is hits start position */
+ if (e->pos < e->start) {
+ if (!__i915_error_seek(e, len))
+ return;
+ }
+
+ if (len >= e->size - e->bytes)
+ len = e->size - e->bytes - 1;
+ memcpy(e->buf + e->bytes, str, len);
+
+ __i915_error_advance(e, len);
+}
+
void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...)
{
va_list args;
@@ -711,6 +759,7 @@ void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...)
}
#define err_printf(e, ...) i915_error_printf(e, __VA_ARGS__)
+#define err_puts(e, s) i915_error_puts(e, s)
static void print_error_buffers(struct drm_i915_error_state_buf *m,
const char *name,
@@ -720,26 +769,26 @@ static void print_error_buffers(struct drm_i915_error_state_buf *m,
err_printf(m, "%s [%d]:\n", name, count);
while (count--) {
- err_printf(m, " %08x %8u %02x %02x %x %x%s%s%s%s%s%s%s",
+ err_printf(m, " %08x %8u %02x %02x %x %x",
err->gtt_offset,
err->size,
err->read_domains,
err->write_domain,
- err->rseqno, err->wseqno,
- pin_flag(err->pinned),
- tiling_flag(err->tiling),
- dirty_flag(err->dirty),
- purgeable_flag(err->purgeable),
- err->ring != -1 ? " " : "",
- ring_str(err->ring),
- cache_level_str(err->cache_level));
+ err->rseqno, err->wseqno);
+ err_puts(m, pin_flag(err->pinned));
+ err_puts(m, tiling_flag(err->tiling));
+ err_puts(m, dirty_flag(err->dirty));
+ err_puts(m, purgeable_flag(err->purgeable));
+ err_puts(m, err->ring != -1 ? " " : "");
+ err_puts(m, ring_str(err->ring));
+ err_puts(m, cache_level_str(err->cache_level));
if (err->name)
err_printf(m, " (name: %d)", err->name);
if (err->fence_reg != I915_FENCE_REG_NONE)
err_printf(m, " (fence: %d)", err->fence_reg);
- err_printf(m, "\n");
+ err_puts(m, "\n");
err++;
}
}
--
1.8.5.rc3