lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Sat, 26 Sep 2020 09:25:29 +0000 From: Damien Le Moal <Damien.LeMoal@....com> To: "paul.walmsley@...ive.com" <paul.walmsley@...ive.com>, "palmer@...belt.com" <palmer@...belt.com>, "palmerdabbelt@...gle.com" <palmerdabbelt@...gle.com>, Anup Patel <Anup.Patel@....com>, "aou@...s.berkeley.edu" <aou@...s.berkeley.edu> CC: "anup@...infault.org" <anup@...infault.org>, "linux-riscv@...ts.infradead.org" <linux-riscv@...ts.infradead.org>, Atish Patra <Atish.Patra@....com>, Alistair Francis <Alistair.Francis@....com>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org> Subject: Re: [PATCH] RISC-V: Check clint_time_val before use On Sat, 2020-09-26 at 12:57 +0530, Anup Patel wrote: > The NoMMU kernel is broken for QEMU virt machine from Linux-5.9-rc6 > because the get_cycles() and friends are called very early from > rand_initialize() before CLINT driver is probed. To fix this, we > should check clint_time_val before use in get_cycles() and friends. > > Fixes: d5be89a8d118 ("RISC-V: Resurrect the MMIO timer implementation > for M-mode systems") > Signed-off-by: Anup Patel <anup.patel@....com> > --- > arch/riscv/include/asm/timex.h | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/arch/riscv/include/asm/timex.h b/arch/riscv/include/asm/timex.h > index 7f659dda0032..52b42bb1602c 100644 > --- a/arch/riscv/include/asm/timex.h > +++ b/arch/riscv/include/asm/timex.h > @@ -17,18 +17,24 @@ typedef unsigned long cycles_t; > #ifdef CONFIG_64BIT > static inline cycles_t get_cycles(void) > { > - return readq_relaxed(clint_time_val); > + if (clint_time_val) > + return readq_relaxed(clint_time_val); > + return 0; > } > #else /* !CONFIG_64BIT */ > static inline u32 get_cycles(void) > { > - return readl_relaxed(((u32 *)clint_time_val)); > + if (clint_time_val) > + return readl_relaxed(((u32 *)clint_time_val)); > + return 0; > } > #define get_cycles get_cycles > > static inline u32 get_cycles_hi(void) > { > - return readl_relaxed(((u32 *)clint_time_val) + 1); > + if (clint_time_val) > + return readl_relaxed(((u32 *)clint_time_val) + 1); > + return 0 > } > #define get_cycles_hi get_cycles_hi > #endif /* CONFIG_64BIT */ Applying this on top of rc6, I now get a hang on Kendryte boot... No problems without the patch on the other hand. -- Damien Le Moal Western Digital
Powered by blists - more mailing lists