Created attachment 299361 [details] kernel dmesg (kernel 5.15-rc7, Talos II) UBSAN catches this at boot on my Talos II. [...] ### dt-test ### EXPECT / : GPIO line <<int>> (line-C-input) hogged as input ================================================================================ UBSAN: shift-out-of-bounds in drivers/of/unittest.c:1933:36 shift exponent -1 is negative CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc7-TalosII #1 Call Trace: [c000000004163700] [c0000000008ffaa8] .dump_stack_lvl+0xa4/0x100 (unreliable) [c000000004163790] [c0000000008fb46c] .ubsan_epilogue+0x10/0x70 [c000000004163800] [c0000000008fb270] .__ubsan_handle_shift_out_of_bounds+0x1f0/0x34c [c000000004163910] [c000000000ad94a0] .of_unittest_untrack_overlay+0x6c/0xe0 [c0000000041639a0] [c000000002098ff8] .of_unittest+0x4c50/0x59f8 [c000000004163b60] [c000000000011b5c] .do_one_initcall+0x7c/0x4f0 [c000000004163c50] [c00000000200300c] .kernel_init_freeable+0x704/0x858 [c000000004163d90] [c000000000012730] .kernel_init+0x20/0x190 [c000000004163e10] [c00000000000ce78] .ret_from_kernel_thread+0x58/0x60 ================================================================================ ### dt-test ### EXPECT \ : OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/substation@100/status [...]
Created attachment 299363 [details] kernel .config (kernel 5.15-rc7, Talos II) # lspci 0000:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0000:01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Turks XT [Radeon HD 6670/7670] 0000:01:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Turks HDMI Audio [Radeon HD 6500/6600 / 6700M Series] 0001:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0001:01:00.0 Non-Volatile memory controller: Phison Electronics Corporation Device 5008 (rev 01) 0002:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0003:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0003:01:00.0 USB controller: Texas Instruments TUSB73x0 SuperSpeed USB 3.0 xHCI Host Controller (rev 02) 0004:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0004:01:00.0 Ethernet controller: Broadcom Inc. and subsidiaries NetXtreme BCM5719 Gigabit Ethernet PCIe (rev 01) 0004:01:00.1 Ethernet controller: Broadcom Inc. and subsidiaries NetXtreme BCM5719 Gigabit Ethernet PCIe (rev 01) 0005:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0005:01:00.0 PCI bridge: ASPEED Technology, Inc. AST1150 PCI-to-PCI Bridge (rev 04) 0005:02:00.0 VGA compatible controller: ASPEED Technology, Inc. ASPEED Graphics Family (rev 41) 0030:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0031:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0032:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4) 0033:00:00.0 PCI bridge: IBM POWER9 Host Bridge (PHB4)
This is the function that triggers it: static void of_unittest_untrack_overlay(int id) { if (overlay_first_id < 0) return; id -= overlay_first_id; if (WARN_ON(id >= MAX_UNITTEST_OVERLAYS)) return; overlay_id_bits[BIT_WORD(id)] &= ~BIT_MASK(id); } My guess is that 'id' is negative here, which means it fails to tigger the WARN_ON() but ends up still being out of range. Can you try changing it to 'unsigned int id'?
I forwarded my email notification of this bug to the mail lists. I prefer discussion to occur there: https://lore.kernel.org/all/c474a371-b524-1da8-4a67-e72cf8f2b0f7@gmail.com/ Thank you for the report.
Fix landed in mainline meanwhile. At least I can replicate this no longer on v5.17-rc2. Thanks!