From c218bca74eeafa2f8528b6bbb34d112075fcf40a Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Wed, 26 Mar 2014 18:25:55 +0000 Subject: arm64: Relax the kernel cache requirements for boot With system caches for the host OS or architected caches for guest OS we cannot easily guarantee that there are no dirty or stale cache lines for the areas of memory written by the kernel during boot with the MMU off (therefore non-cacheable accesses). This patch adds the necessary cache maintenance during boot and relaxes the booting requirements. Signed-off-by: Catalin Marinas --- arch/arm64/kernel/head.S | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-) (limited to 'arch/arm64/kernel') diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 61035d6814c..26109682d2f 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -229,7 +230,11 @@ ENTRY(set_cpu_boot_mode_flag) cmp w20, #BOOT_CPU_MODE_EL2 b.ne 1f add x1, x1, #4 -1: str w20, [x1] // This CPU has booted in EL1 +1: dc cvac, x1 // Clean potentially dirty cache line + dsb sy + str w20, [x1] // This CPU has booted in EL1 + dc civac, x1 // Clean&invalidate potentially stale cache line + dsb sy ret ENDPROC(set_cpu_boot_mode_flag) @@ -240,8 +245,9 @@ ENDPROC(set_cpu_boot_mode_flag) * This is not in .bss, because we set it sufficiently early that the boot-time * zeroing of .bss would clobber it. */ - .pushsection .data + .pushsection .data..cacheline_aligned ENTRY(__boot_cpu_mode) + .align L1_CACHE_SHIFT .long BOOT_CPU_MODE_EL2 .long 0 .popsection @@ -408,6 +414,15 @@ ENDPROC(__calc_phys_offset) */ __create_page_tables: pgtbl x25, x26, x24 // idmap_pg_dir and swapper_pg_dir addresses + mov x27, lr + + /* + * Invalidate the idmap and swapper page tables to avoid potential + * dirty cache lines being evicted. + */ + mov x0, x25 + add x1, x26, #SWAPPER_DIR_SIZE + bl __inval_cache_range /* * Clear the idmap and swapper page tables. @@ -470,6 +485,17 @@ __create_page_tables: add x0, x26, #2 * PAGE_SIZE // section table address create_pgd_entry x26, x0, x5, x6, x7 #endif + + /* + * Since the page tables have been populated with non-cacheable + * accesses (MMU disabled), invalidate the idmap and swapper page + * tables again to remove any speculatively loaded cache lines. + */ + mov x0, x25 + add x1, x26, #SWAPPER_DIR_SIZE + bl __inval_cache_range + + mov lr, x27 ret ENDPROC(__create_page_tables) .ltorg -- cgit v1.2.3-70-g09d2 From ff268ff7f32bf5388b7422f0c0773d88add23423 Mon Sep 17 00:00:00 2001 From: Mark Salter Date: Sat, 5 Apr 2014 15:25:49 +0100 Subject: arm64: fix !CONFIG_COMPAT build failures MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Recent arm64 builds using CONFIG_ARM64_64K_PAGES are failing with: arch/arm64/kernel/perf_regs.c: In function ‘perf_reg_abi’: arch/arm64/kernel/perf_regs.c:41:2: error: implicit declaration of function ‘is_compat_thread’ arch/arm64/kernel/perf_event.c:1398:2: error: unknown type name ‘compat_uptr_t’ This is due to some recent arm64 perf commits with compat support: commit 23c7d70d55c6d9: ARM64: perf: add support for frame pointer unwinding in compat mode commit 2ee0d7fd36a3f8: ARM64: perf: add support for perf registers API Those patches make the arm64 kernel unbuildable if CONFIG_COMPAT is not defined and CONFIG_ARM64_64K_PAGES depends on !CONFIG_COMPAT. This patch allows the arm64 kernel to build with and without CONFIG_COMPAT. Signed-off-by: Mark Salter Signed-off-by: Catalin Marinas --- arch/arm64/kernel/perf_event.c | 4 ++++ arch/arm64/kernel/perf_regs.c | 2 ++ 2 files changed, 6 insertions(+) (limited to 'arch/arm64/kernel') diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index e868c72a793..baf5afb7e6a 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -1386,6 +1386,7 @@ user_backtrace(struct frame_tail __user *tail, return buftail.fp; } +#ifdef CONFIG_COMPAT /* * The registers we're interested in are at the end of the variable * length saved register structure. The fp points at the end of this @@ -1430,6 +1431,7 @@ compat_user_backtrace(struct compat_frame_tail __user *tail, return (struct compat_frame_tail __user *)compat_ptr(buftail.fp) - 1; } +#endif /* CONFIG_COMPAT */ void perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs) @@ -1451,6 +1453,7 @@ void perf_callchain_user(struct perf_callchain_entry *entry, tail && !((unsigned long)tail & 0xf)) tail = user_backtrace(tail, entry); } else { +#ifdef CONFIG_COMPAT /* AARCH32 compat mode */ struct compat_frame_tail __user *tail; @@ -1459,6 +1462,7 @@ void perf_callchain_user(struct perf_callchain_entry *entry, while ((entry->nr < PERF_MAX_STACK_DEPTH) && tail && !((unsigned long)tail & 0x3)) tail = compat_user_backtrace(tail, entry); +#endif } } diff --git a/arch/arm64/kernel/perf_regs.c b/arch/arm64/kernel/perf_regs.c index f2d6f0a36d6..422ebd63b61 100644 --- a/arch/arm64/kernel/perf_regs.c +++ b/arch/arm64/kernel/perf_regs.c @@ -2,6 +2,8 @@ #include #include #include + +#include #include #include -- cgit v1.2.3-70-g09d2