From b61130381120398876b86282082ad9f24976dfcf Mon Sep 17 00:00:00 2001 From: James Morse Date: Wed, 24 Aug 2016 18:27:29 +0100 Subject: arm64: vmlinux.ld: Add mmuoff data sections and move mmuoff text into idmap Resume from hibernate needs to clean any text executed by the kernel with the MMU off to the PoC. Collect these functions together into the .idmap.text section as all this code is tightly coupled and also needs the same cleaning after resume. Data is more complicated, secondary_holding_pen_release is written with the MMU on, clean and invalidated, then read with the MMU off. In contrast __boot_cpu_mode is written with the MMU off, the corresponding cache line is invalidated, so when we read it with the MMU on we don't get stale data. These cache maintenance operations conflict with each other if the values are within a Cache Writeback Granule (CWG) of each other. Collect the data into two sections .mmuoff.data.read and .mmuoff.data.write, the linker script ensures mmuoff.data.write section is aligned to the architectural maximum CWG of 2KB. Signed-off-by: James Morse Cc: Ard Biesheuvel Cc: Mark Rutland Reviewed-by: Catalin Marinas Signed-off-by: Will Deacon --- arch/arm64/kernel/smp_spin_table.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/arm64/kernel/smp_spin_table.c') diff --git a/arch/arm64/kernel/smp_spin_table.c b/arch/arm64/kernel/smp_spin_table.c index 18a71bcd26ee..9a00eee9acc8 100644 --- a/arch/arm64/kernel/smp_spin_table.c +++ b/arch/arm64/kernel/smp_spin_table.c @@ -29,7 +29,8 @@ #include extern void secondary_holding_pen(void); -volatile unsigned long secondary_holding_pen_release = INVALID_HWID; +volatile unsigned long __section(".mmuoff.data.read") +secondary_holding_pen_release = INVALID_HWID; static phys_addr_t cpu_release_addr[NR_CPUS]; -- cgit