From bf688e341abded99d7f83f6cdb306c564a49d0a0 Mon Sep 17 00:00:00 2001
From: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu, 2 Sep 2021 16:20:50 +0200
Subject: drm/i915: Drop code to handle set-vm races from execbuf
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Git-commit: e1068a9e808a14cd532ede325e5e16df45c63f18
Patch-mainline: v5.16-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
Changing the vm from a finalized gem ctx is no longer possible, which
means we don't have to check for that anymore.
I was pondering whether to keep the check as a WARN_ON, but things go
boom real bad real fast if the vm of a vma is wrong. Plus we'd need to
also get the ggtt vm for !full-ppgtt platforms. Ditching it all seemed
like a better idea.
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
References: ccbc1b97948a ("drm/i915/gem: Don't allow changing the VM on running contexts (v4)")
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Thomas Hellström" <thomas.hellstrom@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20210902142057.929669-4-daniel.vetter@ffwll.ch
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 1aa249908b64..fb0b0c517de0 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -759,11 +759,7 @@ static int __eb_add_lut(struct i915_execbuffer *eb,
/* Check that the context hasn't been closed in the meantime */
err = -EINTR;
if (!mutex_lock_interruptible(&ctx->lut_mutex)) {
- struct i915_address_space *vm = rcu_access_pointer(ctx->vm);
-
- if (unlikely(vm && vma->vm != vm))
- err = -EAGAIN; /* user racing with ctx set-vm */
- else if (likely(!i915_gem_context_is_closed(ctx)))
+ if (likely(!i915_gem_context_is_closed(ctx)))
err = radix_tree_insert(&ctx->handles_vma, handle, vma);
else
err = -ENOENT;
--
2.38.1