Re: [PATCH v1] riscv: fix reserved memory setup

From: Palmer Dabbelt
Date: Thu Nov 10 2022 - 17:59:22 EST


On Mon, 7 Nov 2022 15:15:25 +0000, Conor Dooley wrote:
> Currently, RISC-V sets up reserved memory using the "early" copy of the
> device tree. As a result, when trying to get a reserved memory region
> using of_reserved_mem_lookup(), the pointer to reserved memory regions
> is using the early, pre-virtual-memory address which causes a kernel
> panic when trying to use the buffer's name:
>
> Unable to handle kernel paging request at virtual address 00000000401c31ac
> Oops [#1]
> Modules linked in:
> CPU: 0 PID: 0 Comm: swapper Not tainted 6.0.0-rc1-00001-g0d9d6953d834 #1
> Hardware name: Microchip PolarFire-SoC Icicle Kit (DT)
> epc : string+0x4a/0xea
> ra : vsnprintf+0x1e4/0x336
> epc : ffffffff80335ea0 ra : ffffffff80338936 sp : ffffffff81203be0
> gp : ffffffff812e0a98 tp : ffffffff8120de40 t0 : 0000000000000000
> t1 : ffffffff81203e28 t2 : 7265736572203a46 s0 : ffffffff81203c20
> s1 : ffffffff81203e28 a0 : ffffffff81203d22 a1 : 0000000000000000
> a2 : ffffffff81203d08 a3 : 0000000081203d21 a4 : ffffffffffffffff
> a5 : 00000000401c31ac a6 : ffff0a00ffffff04 a7 : ffffffffffffffff
> s2 : ffffffff81203d08 s3 : ffffffff81203d00 s4 : 0000000000000008
> s5 : ffffffff000000ff s6 : 0000000000ffffff s7 : 00000000ffffff00
> s8 : ffffffff80d9821a s9 : ffffffff81203d22 s10: 0000000000000002
> s11: ffffffff80d9821c t3 : ffffffff812f3617 t4 : ffffffff812f3617
> t5 : ffffffff812f3618 t6 : ffffffff81203d08
> status: 0000000200000100 badaddr: 00000000401c31ac cause: 000000000000000d
> [<ffffffff80338936>] vsnprintf+0x1e4/0x336
> [<ffffffff80055ae2>] vprintk_store+0xf6/0x344
> [<ffffffff80055d86>] vprintk_emit+0x56/0x192
> [<ffffffff80055ed8>] vprintk_default+0x16/0x1e
> [<ffffffff800563d2>] vprintk+0x72/0x80
> [<ffffffff806813b2>] _printk+0x36/0x50
> [<ffffffff8068af48>] print_reserved_mem+0x1c/0x24
> [<ffffffff808057ec>] paging_init+0x528/0x5bc
> [<ffffffff808031ae>] setup_arch+0xd0/0x592
> [<ffffffff8080070e>] start_kernel+0x82/0x73c
>
> [...]

Applied, thanks!

[1/1] riscv: fix reserved memory setup
https://git.kernel.org/palmer/c/50e63dd8ed92

Best regards,
--
Palmer Dabbelt <palmer@xxxxxxxxxxxx>