Prevent divider overflow.
Fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=28932
Signed-off-by: Alex Deucher <alexdeucher at gmail.com>
Cc: stable at kernel.org
---
drivers/gpu/drm/radeon/radeon_display.c | 10 ++++++++++
1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/radeon/radeon_display.c
b/drivers/gpu/drm/radeon/radeon_display.c
index 2eff98c..0e65709 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -793,6 +793,11 @@ static void avivo_get_fb_div(struct radeon_pll *pll,
tmp *= target_clock;
*fb_div = tmp / pll->reference_freq;
*frac_fb_div = tmp % pll->reference_freq;
+
+ if (*fb_div > pll->max_feedback_div)
+ *fb_div = pll->max_feedback_div;
+ else if (*fb_div < pll->min_feedback_div)
+ *fb_div = pll->min_feedback_div;
}
static u32 avivo_get_post_div(struct radeon_pll *pll,
@@ -826,6 +831,11 @@ static u32 avivo_get_post_div(struct radeon_pll *pll,
post_div--;
}
+ if (post_div > pll->max_post_div)
+ post_div = pll->max_post_div;
+ else if (post_div < pll->min_post_div)
+ post_div = pll->min_post_div;
+
return post_div;
}
--
1.7.1.1
