[Intel-gfx] [bug report] drm/i915: Use per object locking in execbuf, v12.

[Dan Carpenter]

Hey Dave,

I think this is a bad merge:

The patch c43ce12328df: "drm/i915: Use per object locking in execbuf,
v12." from Aug 19, 2020, leads to the following static checker
warning:

	drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c:1459 __reloc_entry_gpu()
	warn: signedness bug returning '(-35)'

drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
  1440  static bool __reloc_entry_gpu(struct i915_execbuffer *eb,
               ^^^^
This should be int.

  1441                                struct i915_vma *vma,
  1442                                u64 offset,
  1443                                u64 target_addr)
  1444  {
  1445          const unsigned int gen = eb->reloc_cache.gen;
  1446          unsigned int len;
  1447          u32 *batch;
  1448          u64 addr;
  1449  
  1450          if (gen >= 8)
  1451                  len = offset & 7 ? 8 : 5;
  1452          else if (gen >= 4)
  1453                  len = 4;
  1454          else
  1455                  len = 3;
  1456  
  1457          batch = reloc_gpu(eb, vma, len);
  1458          if (batch == ERR_PTR(-EDEADLK))
  1459                  return (s64)-EDEADLK;

No need for this cast, btw.

  1460          else if (IS_ERR(batch))
  1461                  return false;
  1462  
  1463          addr = gen8_canonical_addr(vma->node.start + offset);
  1464          if (gen >= 8) {
  1465                  if (offset & 7) {
  1466                          *batch++ = MI_STORE_DWORD_IMM_GEN4;
  1467                          *batch++ = lower_32_bits(addr);
  1468                          *batch++ = upper_32_bits(addr);
  1469                          *batch++ = lower_32_bits(target_addr);
  1470  
  1471                          addr = gen8_canonical_addr(addr + 4);
  1472  
  1473                          *batch++ = MI_STORE_DWORD_IMM_GEN4;
  1474                          *batch++ = lower_32_bits(addr);
  1475                          *batch++ = upper_32_bits(addr);

regards,
dan carpenter