The patch below does not apply to the 4.12-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b5fa57ddc4a2492441a1391f07d5c8a282271249 Mon Sep 17 00:00:00 2001 From: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx> Date: Thu, 3 Aug 2017 17:58:07 +0100 Subject: [PATCH] drm/i915/perf: fix flex eu registers programming We were reserving fewer dwords in the ring than necessary. Indeed we're always writing all registers once, so discard the actual number of registers given by the user and just program the whitelisted ones once. Fixes: 19f81df2859e ("drm/i915/perf: Add OA unit support for Gen 8+") Reported-by: Matthew Auld <matthew.william.auld@xxxxxxxxx> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx> Reviewed-by: Matthew Auld <matthew.auld@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # v4.12+ Link: https://patchwork.freedesktop.org/patch/msgid/20170803165812.2373-6-lionel.g.landwerlin@xxxxxxxxx (cherry picked from commit 01d928e9a1644eb2e28f684905f888e700c7b9dc) Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c index 9cd22f83b0cf..f33d90226704 100644 --- a/drivers/gpu/drm/i915/i915_perf.c +++ b/drivers/gpu/drm/i915/i915_perf.c @@ -1601,11 +1601,11 @@ static int gen8_emit_oa_config(struct drm_i915_gem_request *req) u32 *cs; int i; - cs = intel_ring_begin(req, n_flex_regs * 2 + 4); + cs = intel_ring_begin(req, ARRAY_SIZE(flex_mmio) * 2 + 4); if (IS_ERR(cs)) return PTR_ERR(cs); - *cs++ = MI_LOAD_REGISTER_IMM(n_flex_regs + 1); + *cs++ = MI_LOAD_REGISTER_IMM(ARRAY_SIZE(flex_mmio) + 1); *cs++ = i915_mmio_reg_offset(GEN8_OACTXCONTROL); *cs++ = (dev_priv->perf.oa.period_exponent << GEN8_OA_TIMER_PERIOD_SHIFT) |