drm/i915/hwmon: Silence UBSAN uninitialized bool variable warning

Loading i915 on UBSAN enabled kernels (CONFIG_UBSAN/CONFIG_UBSAN_BOOL)
causes the following warning:

  UBSAN: invalid-load in drivers/gpu/drm/i915/gt/uc/intel_uc.c:558:2
  load of value 255 is not a valid value for type '_Bool'
  Call Trace:
   dump_stack_lvl+0x57/0x7d
   ubsan_epilogue+0x5/0x40
   __ubsan_handle_load_invalid_value.cold+0x43/0x48
   __uc_init_hw+0x76a/0x903 [i915]
   ...
   i915_driver_probe+0xfb1/0x1eb0 [i915]
   i915_pci_probe+0xbe/0x2d0 [i915]

The warning happens because during probe i915_hwmon is still not available
which results in the output boolean variable *old remaining
uninitialized. Silence the warning by initializing the variable to an
arbitrary value.

v2: Move variable initialization to the declaration (Andi)

Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230512203735.2635237-1-ashutosh.dixit@intel.com

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc.c b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
index 1381943b8973d2a597c64c12dc3a327bd58cd37f..c8b9cbb7ba3a9a7bcdc079e3fb901ac788e30862 100644 (file)
--- a/drivers/gpu/drm/i915/gt/uc/intel_uc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_uc.c
@@ -465,7 +465,7 @@ static int __uc_init_hw(struct intel_uc *uc)
        struct intel_guc *guc = &uc->guc;
        struct intel_huc *huc = &uc->huc;
        int ret, attempts;
-       bool pl1en;
+       bool pl1en = false;
 
        GEM_BUG_ON(!intel_uc_supports_guc(uc));
        GEM_BUG_ON(!intel_uc_wants_guc(uc));