On Tue, 13 Feb 2024 23:24:10 +0530, Naveen N Rao wrote:
> Michael reported that we are seeing ftrace bug on bootup when KASAN is
> enabled, and if we are using -fpatchable-function-entry:
>
> ftrace: allocating 47780 entries in 18 pages
> ftrace-powerpc: 0xc0000000020b3d5c: No module provided for non-kernel
> address
> ------------[ ftrace bug ]------------
> ftrace faulted on modifying
> [<c0000000020b3d5c>] 0xc0000000020b3d5c
> Initializing ftrace call sites
> ftrace record flags: 0
> (0)
> expected tramp: c00000000008cef4
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 0 at kernel/trace/ftrace.c:2180
> ftrace_bug+0x3c0/0x424
> Modules linked in:
> CPU: 0 PID: 0 Comm: swapper Not tainted 6.5.0-rc3-00120-g0f71dcfb4aef #860
> Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202
> 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries
> NIP: c0000000003aa81c LR: c0000000003aa818 CTR: 0000000000000000
> REGS: c0000000033cfab0 TRAP: 0700 Not tainted
> (6.5.0-rc3-00120-g0f71dcfb4aef)
> MSR: 8000000002021033 <SF,VEC,ME,IR,DR,RI,LE> CR: 28028240 XER:
> 00000000
> CFAR: c0000000002781a8 IRQMASK: 3
> ...
> NIP [c0000000003aa81c] ftrace_bug+0x3c0/0x424
> LR [c0000000003aa818] ftrace_bug+0x3bc/0x424
> Call Trace:
> ftrace_bug+0x3bc/0x424 (unreliable)
> ftrace_process_locs+0x5f4/0x8a0
> ftrace_init+0xc0/0x1d0
> start_kernel+0x1d8/0x484
>
> [...]
Applied to powerpc/fixes.
[1/1] powerpc/ftrace: Ignore ftrace locations in exit text sections
https://git.kernel.org/powerpc/c/ea73179e64131bcd29ba6defd33732abdf8ca14b
cheers
