Ended up with free time today 
git bisect says it’s e0f48568c7f2a638213dee317fde03c23775556f. I’m not totally confident in my work so here’s my git bisect log:
# bad: [4fa244fddfebb21378042556862e197284ef65ac] VERSION: bump for 25.0.0
# good: [769e51468b49b2a42f0a0eaf71cf9eed5ff4e5de] VERSION: bump for 24.3.4
git bisect start 'mesa-25.0.0' 'mesa-24.3.4'
# good: [879ec4270d07b51d14ab20fa0b72816b7dd664a3] panvk: fix dummy sampler handle for vs
git bisect good 879ec4270d07b51d14ab20fa0b72816b7dd664a3
# bad: [419879ee6292506c79a3f1342161663cac77b33c] ir3,freedreno: remove binning outputs after vs ucp lowering
git bisect bad 419879ee6292506c79a3f1342161663cac77b33c
# bad: [f3272f0044c67fb1caf41c07d884d9d9910cf1ea] radv: add new start/stop sqtt helpers for capturing with SQTT
git bisect bad f3272f0044c67fb1caf41c07d884d9d9910cf1ea
# good: [6bd21e4a062e796361c8585a6cd7c68ffa4bedea] frontends/va: Check if target buffer is supported in EndPicture
git bisect good 6bd21e4a062e796361c8585a6cd7c68ffa4bedea
# good: [4c8ff06449397685a3e7f084cb4e3693ccf82300] ci/pipeline_message: add unit tests for tool
git bisect good 4c8ff06449397685a3e7f084cb4e3693ccf82300
# bad: [0ae8e69810ed0449ada45c8288cb0395e989b439] pan/cs: Add cs_exception_handler_ctx
git bisect bad 0ae8e69810ed0449ada45c8288cb0395e989b439
# good: [4af57952b126bf399c1063e83dbe305b3d4db013] panfrost: Add support for AFBC(split)
git bisect good 4af57952b126bf399c1063e83dbe305b3d4db013
# bad: [dcf380d1b6d57e84c67b9d94872cea2e1e0e2f0b] docs: update GL_OES_shader_image_atomic support
git bisect bad dcf380d1b6d57e84c67b9d94872cea2e1e0e2f0b
# bad: [9838024547b355d6abb05e4415106925881a5a94] r300: always transform sin/cos input for fs
git bisect bad 9838024547b355d6abb05e4415106925881a5a94
# bad: [5de990f5a94f357f6efd6950f166c2742b4442e8] aco: add SSA repair pass
git bisect bad 5de990f5a94f357f6efd6950f166c2742b4442e8
# bad: [5c3a757ba6fe05d3db7536cbce020d0e6b62573f] radv: add a pipeline helper to skip shaders cache
git bisect bad 5c3a757ba6fe05d3db7536cbce020d0e6b62573f
# bad: [3f646d43dd21809e95a9f862ebe17733fbece72a] radv: fix dumping debug/perftest options when there are holes
git bisect bad 3f646d43dd21809e95a9f862ebe17733fbece72a
# bad: [e0f48568c7f2a638213dee317fde03c23775556f] panfrost: Advertise support for AFBC(32x8,sparse,split)
git bisect bad e0f48568c7f2a638213dee317fde03c23775556f
# first bad commit: [e0f48568c7f2a638213dee317fde03c23775556f] panfrost: Advertise support for AFBC(32x8,sparse,split)
(I did not reboot at any point here but did see clear differences between good and bad commits).
Edit: double-checked my work: e0f485 does indeed flicker, and its parent, 4af579 does not.