Qiuxu Zhuo 2e6fe1bbef EDAC/i10nm: Skip DIMM enumeration on a disabled memory controller
When loading the i10nm_edac driver on some Intel Granite Rapids servers,
a call trace may appear as follows:

  UBSAN: shift-out-of-bounds in drivers/edac/skx_common.c:453:16
  shift exponent -66 is negative
  ...
  __ubsan_handle_shift_out_of_bounds+0x1e3/0x390
  skx_get_dimm_info.cold+0x47/0xd40 [skx_edac_common]
  i10nm_get_dimm_config+0x23e/0x390 [i10nm_edac]
  skx_register_mci+0x159/0x220 [skx_edac_common]
  i10nm_init+0xcb0/0x1ff0 [i10nm_edac]
  ...

This occurs because some BIOS may disable a memory controller if there
aren't any memory DIMMs populated on this memory controller. The DIMMMTR
register of this disabled memory controller contains the invalid value
~0, resulting in the call trace above.

Fix this call trace by skipping DIMM enumeration on a disabled memory
controller.

Fixes: ba987eaaab ("EDAC/i10nm: Add Intel Granite Rapids server support")
Reported-by: Jose Jesus Ambriz Meza <jose.jesus.ambriz.meza@intel.com>
Reported-by: Chia-Lin Kao (AceLan) <acelan.kao@canonical.com>
Closes: https://lore.kernel.org/all/20250730063155.2612379-1-acelan.kao@canonical.com/
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Tested-by: Chia-Lin Kao (AceLan) <acelan.kao@canonical.com>
Link: https://lore.kernel.org/r/20250806065707.3533345-1-qiuxu.zhuo@intel.com
2025-08-19 16:18:14 -07:00
2025-02-19 14:53:27 -07:00
2025-08-10 19:41:16 +03:00

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