diff options
| -rw-r--r-- | arch/arm/kernel/vmlinux.lds.S | 18 | ||||
| -rw-r--r-- | arch/arm/kvm/init.S | 3 | ||||
| -rw-r--r-- | arch/arm/kvm/mmu.c | 42 | ||||
| -rw-r--r-- | arch/arm64/kernel/vmlinux.lds.S | 17 |
4 files changed, 34 insertions, 46 deletions
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index b31aa73e8076..ba65f1217310 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -23,11 +23,20 @@ VMLINUX_SYMBOL(__idmap_text_start) = .; \ *(.idmap.text) \ VMLINUX_SYMBOL(__idmap_text_end) = .; \ - . = ALIGN(32); \ + . = ALIGN(1 << LOG2CEIL(__hyp_idmap_size)); \ VMLINUX_SYMBOL(__hyp_idmap_text_start) = .; \ *(.hyp.idmap.text) \ VMLINUX_SYMBOL(__hyp_idmap_text_end) = .; +/* + * If the HYP idmap .text section is populated, it needs to be positioned + * such that it will not cross a page boundary in the final output image. + * So align it to the section size rounded up to the next power of 2. + * If __hyp_idmap_size is undefined, the section will be empty so define + * it as 0 in that case. + */ +PROVIDE(__hyp_idmap_size = 0); + #ifdef CONFIG_HOTPLUG_CPU #define ARM_CPU_DISCARD(x) #define ARM_CPU_KEEP(x) x @@ -346,8 +355,11 @@ SECTIONS */ ASSERT((__proc_info_end - __proc_info_begin), "missing CPU support") ASSERT((__arch_info_end - __arch_info_begin), "no machine record defined") + /* - * The HYP init code can't be more than a page long. + * The HYP init code can't be more than a page long, + * and should not cross a page boundary. * The above comment applies as well. */ -ASSERT(((__hyp_idmap_text_end - __hyp_idmap_text_start) <= PAGE_SIZE), "HYP init code too big") +ASSERT((__hyp_idmap_text_start & ~PAGE_MASK) + __hyp_idmap_size <= PAGE_SIZE, + "HYP init code too big or misaligned") diff --git a/arch/arm/kvm/init.S b/arch/arm/kvm/init.S index 3988e72d16ff..11fb1d56f449 100644 --- a/arch/arm/kvm/init.S +++ b/arch/arm/kvm/init.S @@ -157,3 +157,6 @@ target: @ We're now in the trampoline code, switch page tables __kvm_hyp_init_end: .popsection + + .global __hyp_idmap_size + .set __hyp_idmap_size, __kvm_hyp_init_end - __kvm_hyp_init diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 3e6859bc3e11..42a24d6b003b 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -37,7 +37,6 @@ static pgd_t *boot_hyp_pgd; static pgd_t *hyp_pgd; static DEFINE_MUTEX(kvm_hyp_pgd_mutex); -static void *init_bounce_page; static unsigned long hyp_idmap_start; static unsigned long hyp_idmap_end; static phys_addr_t hyp_idmap_vector; @@ -405,9 +404,6 @@ void free_boot_hyp_pgd(void) if (hyp_pgd) unmap_range(NULL, hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE); - free_page((unsigned long)init_bounce_page); - init_bounce_page = NULL; - mutex_unlock(&kvm_hyp_pgd_mutex); } @@ -1498,39 +1494,11 @@ int kvm_mmu_init(void) hyp_idmap_end = kvm_virt_to_phys(__hyp_idmap_text_end); hyp_idmap_vector = kvm_virt_to_phys(__kvm_hyp_init); - if ((hyp_idmap_start ^ hyp_idmap_end) & PAGE_MASK) { - /* - * Our init code is crossing a page boundary. Allocate - * a bounce page, copy the code over and use that. - */ - size_t len = __hyp_idmap_text_end - __hyp_idmap_text_start; - phys_addr_t phys_base; - - init_bounce_page = (void *)__get_free_page(GFP_KERNEL); - if (!init_bounce_page) { - kvm_err("Couldn't allocate HYP init bounce page\n"); - err = -ENOMEM; - goto out; - } - - memcpy(init_bounce_page, __hyp_idmap_text_start, len); - /* - * Warning: the code we just copied to the bounce page - * must be flushed to the point of coherency. - * Otherwise, the data may be sitting in L2, and HYP - * mode won't be able to observe it as it runs with - * caches off at that point. - */ - kvm_flush_dcache_to_poc(init_bounce_page, len); - - phys_base = kvm_virt_to_phys(init_bounce_page); - hyp_idmap_vector += phys_base - hyp_idmap_start; - hyp_idmap_start = phys_base; - hyp_idmap_end = phys_base + len; - - kvm_info("Using HYP init bounce page @%lx\n", - (unsigned long)phys_base); - } + /* + * We rely on the linker script to ensure at build time that the HYP + * init code does not cross a page boundary. + */ + BUG_ON((hyp_idmap_start ^ (hyp_idmap_end - 1)) & PAGE_MASK); hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order); boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order); diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index 5d9d2dca530d..a2c29865c3fe 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -23,10 +23,14 @@ jiffies = jiffies_64; #define HYPERVISOR_TEXT \ /* \ - * Force the alignment to be compatible with \ - * the vectors requirements \ + * Align to 4 KB so that \ + * a) the HYP vector table is at its minimum \ + * alignment of 2048 bytes \ + * b) the HYP init code will not cross a page \ + * boundary if its size does not exceed \ + * 4 KB (see related ASSERT() below) \ */ \ - . = ALIGN(2048); \ + . = ALIGN(SZ_4K); \ VMLINUX_SYMBOL(__hyp_idmap_text_start) = .; \ *(.hyp.idmap.text) \ VMLINUX_SYMBOL(__hyp_idmap_text_end) = .; \ @@ -163,10 +167,11 @@ SECTIONS } /* - * The HYP init code can't be more than a page long. + * The HYP init code can't be more than a page long, + * and should not cross a page boundary. */ -ASSERT(((__hyp_idmap_text_start + PAGE_SIZE) > __hyp_idmap_text_end), - "HYP init code too big") +ASSERT(__hyp_idmap_text_end - (__hyp_idmap_text_start & ~(SZ_4K - 1)) <= SZ_4K, + "HYP init code too big or misaligned") /* * If padding is applied before .head.text, virt<->phys conversions will fail. |