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authorAkeem G Abodunrin2020-01-08 09:25:00 -0800
committerAkeem G Abodunrin2020-01-09 07:18:02 -0800
commitbc8a76a152c5f9ef3b48104154a65a68a8b76946 (patch)
treea62b31b65787d3531adcce6763465f64cd228d49 /drivers/gpu
parentc79f46a282390e0f5b306007bf7b11a46d529538 (diff)
drm/i915/gen9: Clear residual context state on context switch
Intel ID: PSIRT-TA-201910-001 CVEID: CVE-2019-14615 Intel GPU Hardware prior to Gen11 does not clear EU state during a context switch. This can result in information leakage between contexts. For Gen8 and Gen9, hardware provides a mechanism for fast cleardown of the EU state, by issuing a PIPE_CONTROL with bit 27 set. We can use this in a context batch buffer to explicitly cleardown the state on every context switch. As this workaround is already in place for gen8, we can borrow the code verbatim for Gen9. Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Signed-off-by: Akeem G Abodunrin <akeem.g.abodunrin@intel.com> Cc: Kumar Valsan Prathap <prathap.kumar.valsan@intel.com> Cc: Chris Wilson <chris.p.wilson@intel.com> Cc: Balestrieri Francesco <francesco.balestrieri@intel.com> Cc: Bloomfield Jon <jon.bloomfield@intel.com> Cc: Dutt Sudeep <sudeep.dutt@intel.com>
Diffstat (limited to 'drivers/gpu')
-rw-r--r--drivers/gpu/drm/i915/gt/intel_lrc.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 75dd0e0367b7..f0485784afbe 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -2664,6 +2664,14 @@ static u32 *gen9_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
/* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt,glk */
batch = gen8_emit_flush_coherentl3_wa(engine, batch);
+ /* WaClearSlmSpaceAtContextSwitch:skl,bxt,kbl,glk,cfl */
+ batch = gen8_emit_pipe_control(batch,
+ PIPE_CONTROL_FLUSH_L3 |
+ PIPE_CONTROL_STORE_DATA_INDEX |
+ PIPE_CONTROL_CS_STALL |
+ PIPE_CONTROL_QW_WRITE,
+ LRC_PPHWSP_SCRATCH_ADDR);
+
batch = emit_lri(batch, lri, ARRAY_SIZE(lri));
/* WaMediaPoolStateCmdInWABB:bxt,glk */