Some assembly symbols contain code that might be executed with an unspecified stack state (e.g. invalid stack pointer, no stackframe, code after alt_cb, ...). Annotate those symbol with UNWIND_HINT_EMPTY to let objtool be aware of them. Signed-off-by: Julien Thierry <jthierry@xxxxxxxxxx> Signed-off-by: Chen Zhongjin <chenzhongjin@xxxxxxxxxx> --- arch/arm64/include/asm/assembler.h | 2 ++ arch/arm64/kernel/cpu-reset.S | 2 ++ arch/arm64/kernel/efi-entry.S | 2 ++ arch/arm64/kernel/entry.S | 7 +++++++ arch/arm64/kernel/head.S | 14 ++++++++++++++ arch/arm64/kernel/hibernate-asm.S | 2 ++ arch/arm64/kernel/relocate_kernel.S | 2 ++ arch/arm64/kernel/sleep.S | 3 +++ arch/arm64/kvm/hyp/hyp-entry.S | 1 + arch/arm64/mm/trans_pgd-asm.S | 3 +++ 10 files changed, 38 insertions(+) diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 8c5a61aeaf8e..68db05428e4b 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -25,6 +25,7 @@ #include <asm/pgtable-hwdef.h> #include <asm/ptrace.h> #include <asm/thread_info.h> +#include <asm/unwind_hints.h> /* * Provide a wxN alias for each wN register so what we can paste a xN @@ -147,6 +148,7 @@ lr .req x30 // link register */ .macro ventry label .align 7 + UNWIND_HINT_EMPTY b \label .endm diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S index 48a8af97faa9..c9022042bdec 100644 --- a/arch/arm64/kernel/cpu-reset.S +++ b/arch/arm64/kernel/cpu-reset.S @@ -10,6 +10,7 @@ #include <linux/linkage.h> #include <asm/assembler.h> #include <asm/sysreg.h> +#include <asm/unwind_hints.h> #include <asm/virt.h> .text @@ -29,6 +30,7 @@ * flat identity mapping. */ SYM_CODE_START(cpu_soft_restart) + UNWIND_HINT_EMPTY mov_q x12, INIT_SCTLR_EL1_MMU_OFF pre_disable_mmu_workaround /* diff --git a/arch/arm64/kernel/efi-entry.S b/arch/arm64/kernel/efi-entry.S index 61a87fa1c305..9a1a94c3c4db 100644 --- a/arch/arm64/kernel/efi-entry.S +++ b/arch/arm64/kernel/efi-entry.S @@ -9,10 +9,12 @@ #include <linux/init.h> #include <asm/assembler.h> +#include <asm/unwind_hints.h> __INIT SYM_CODE_START(efi_enter_kernel) + UNWIND_HINT_EMPTY /* * efi_pe_entry() will have copied the kernel image if necessary and we * end up here with device tree address in x1 and the kernel entry diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index c460ba2d009d..3bd11101e79d 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -28,6 +28,7 @@ #include <asm/thread_info.h> #include <asm/asm-uaccess.h> #include <asm/unistd.h> +#include <asm/unwind_hints.h> .macro clear_gp_regs .irp n,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29 @@ -37,6 +38,7 @@ .macro kernel_ventry, el:req, ht:req, regsize:req, label:req .align 7 + UNWIND_HINT_EMPTY .Lventry_start\@: .if \el == 0 /* @@ -44,6 +46,7 @@ * skipped by the trampoline vectors, to trigger the cleanup. */ b .Lskip_tramp_vectors_cleanup\@ + UNWIND_HINT_EMPTY .if \regsize == 64 mrs x30, tpidrro_el0 msr tpidrro_el0, xzr @@ -417,6 +420,7 @@ alternative_else_nop_endif ldp x24, x25, [sp, #16 * 12] ldp x26, x27, [sp, #16 * 13] ldp x28, x29, [sp, #16 * 14] + UNWIND_HINT_EMPTY .if \el == 0 alternative_if_not ARM64_UNMAP_KERNEL_AT_EL0 @@ -662,6 +666,7 @@ alternative_else_nop_endif .macro tramp_ventry, vector_start, regsize, kpti, bhb .align 7 + UNWIND_HINT_EMPTY 1: .if \regsize == 64 msr tpidrro_el0, x30 // Restored in kernel_ventry @@ -687,6 +692,7 @@ alternative_else_nop_endif * enter the full-fat kernel vectors. */ bl 2f + UNWIND_HINT_EMPTY b . 2: tramp_map_kernel x30 @@ -717,6 +723,7 @@ alternative_else_nop_endif .endm .macro tramp_exit, regsize = 64 + UNWIND_HINT_EMPTY tramp_data_read_var x30, this_cpu_vector get_this_cpu_offset x29 ldr x30, [x30, x29] diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 6db9c3603bd8..2a66d18091eb 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -33,6 +33,7 @@ #include <asm/smp.h> #include <asm/sysreg.h> #include <asm/thread_info.h> +#include <asm/unwind_hints.h> #include <asm/virt.h> #include "efi-header.S" @@ -63,6 +64,7 @@ * DO NOT MODIFY. Image header expected by Linux boot-loaders. */ efi_signature_nop // special NOP to identity as PE/COFF executable + UNWIND_HINT_EMPTY b primary_entry // branch to kernel start, magic .quad 0 // Image load offset from start of RAM, little-endian le64sym _kernel_size_le // Effective size of kernel image, little-endian @@ -109,6 +111,7 @@ SYM_CODE_END(primary_entry) * Preserve the arguments passed by the bootloader in x0 .. x3 */ SYM_CODE_START_LOCAL(preserve_boot_args) + UNWIND_HINT_EMPTY mov x21, x0 // x21=FDT adr_l x0, boot_args // record the contents of @@ -260,6 +263,7 @@ SYM_CODE_END(preserve_boot_args) * been enabled */ SYM_CODE_START_LOCAL(__create_page_tables) + UNWIND_HINT_EMPTY mov x28, lr /* @@ -494,6 +498,7 @@ EXPORT_SYMBOL(kimage_vaddr) * booted in EL1 or EL2 respectively. */ SYM_CODE_START(init_kernel_el) + UNWIND_HINT_EMPTY mrs x0, CurrentEL cmp x0, #CurrentEL_EL2 b.eq init_el2 @@ -553,6 +558,7 @@ SYM_INNER_LABEL(init_el2, SYM_L_LOCAL) eret __cpu_stick_to_vhe: + UNWIND_HINT_EMPTY mov x0, #HVC_VHE_RESTART hvc #0 mov x0, #BOOT_CPU_MODE_EL2 @@ -564,6 +570,7 @@ SYM_CODE_END(init_kernel_el) * in w0. See arch/arm64/include/asm/virt.h for more info. */ SYM_CODE_START_LOCAL(set_cpu_boot_mode_flag) + UNWIND_HINT_EMPTY adr_l x1, __boot_cpu_mode cmp w0, #BOOT_CPU_MODE_EL2 b.ne 1f @@ -607,6 +614,7 @@ SYM_DATA_END(__early_cpu_boot_status) * cores are held until we're ready for them to initialise. */ SYM_CODE_START(secondary_holding_pen) + UNWIND_HINT_EMPTY bl init_kernel_el // w0=cpu_boot_mode bl set_cpu_boot_mode_flag mrs x0, mpidr_el1 @@ -625,6 +633,7 @@ SYM_CODE_END(secondary_holding_pen) * be used where CPUs are brought online dynamically by the kernel. */ SYM_CODE_START(secondary_entry) + UNWIND_HINT_EMPTY bl init_kernel_el // w0=cpu_boot_mode bl set_cpu_boot_mode_flag b secondary_startup @@ -644,6 +653,7 @@ SYM_CODE_START_LOCAL(secondary_startup) SYM_CODE_END(secondary_startup) SYM_CODE_START_LOCAL(__secondary_switched) + UNWIND_HINT_EMPTY adr_l x5, vectors msr vbar_el1, x5 isb @@ -663,6 +673,7 @@ SYM_CODE_START_LOCAL(__secondary_switched) SYM_CODE_END(__secondary_switched) SYM_CODE_START_LOCAL(__secondary_too_slow) + UNWIND_HINT_EMPTY wfe wfi b __secondary_too_slow @@ -699,6 +710,7 @@ SYM_CODE_END(__secondary_too_slow) * If it isn't, park the CPU */ SYM_CODE_START(__enable_mmu) + UNWIND_HINT_EMPTY mrs x2, ID_AA64MMFR0_EL1 ubfx x2, x2, #ID_AA64MMFR0_TGRAN_SHIFT, 4 cmp x2, #ID_AA64MMFR0_TGRAN_SUPPORTED_MIN @@ -720,6 +732,7 @@ SYM_CODE_START(__enable_mmu) SYM_CODE_END(__enable_mmu) SYM_CODE_START_LOCAL(__cpu_secondary_check52bitva) + UNWIND_HINT_EMPTY #ifdef CONFIG_ARM64_VA_BITS_52 ldr_l x0, vabits_actual cmp x0, #52 @@ -751,6 +764,7 @@ SYM_CODE_END(__no_granule_support) #ifdef CONFIG_RELOCATABLE SYM_CODE_START_LOCAL(__relocate_kernel) + UNWIND_HINT_EMPTY /* * Iterate over each entry in the relocation table, and apply the * relocations in place. diff --git a/arch/arm64/kernel/hibernate-asm.S b/arch/arm64/kernel/hibernate-asm.S index 0e1d9c3c6a93..c0bec20bf0e0 100644 --- a/arch/arm64/kernel/hibernate-asm.S +++ b/arch/arm64/kernel/hibernate-asm.S @@ -13,6 +13,7 @@ #include <asm/cputype.h> #include <asm/memory.h> #include <asm/page.h> +#include <asm/unwind_hints.h> #include <asm/virt.h> /* @@ -46,6 +47,7 @@ */ .pushsection ".hibernate_exit.text", "ax" SYM_CODE_START(swsusp_arch_suspend_exit) + UNWIND_HINT_EMPTY /* * We execute from ttbr0, change ttbr1 to our copied linear map tables * with a break-before-make via the zero page diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S index f0a3df9e18a3..f8cd8fcf2d4f 100644 --- a/arch/arm64/kernel/relocate_kernel.S +++ b/arch/arm64/kernel/relocate_kernel.S @@ -16,6 +16,7 @@ #include <asm/page.h> #include <asm/sysreg.h> #include <asm/virt.h> +#include <asm/unwind_hints.h> .macro turn_off_mmu tmp1, tmp2 mov_q \tmp1, INIT_SCTLR_EL1_MMU_OFF @@ -37,6 +38,7 @@ * safe memory that has been set up to be preserved during the copy operation. */ SYM_CODE_START(arm64_relocate_new_kernel) + UNWIND_HINT_EMPTY /* Setup the list loop variables. */ ldr x18, [x0, #KIMAGE_ARCH_ZERO_PAGE] /* x18 = zero page for BBM */ ldr x17, [x0, #KIMAGE_ARCH_TTBR1] /* x17 = linear map copy */ diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S index f0087e8bcd28..799ec01b0649 100644 --- a/arch/arm64/kernel/sleep.S +++ b/arch/arm64/kernel/sleep.S @@ -4,6 +4,7 @@ #include <asm/asm-offsets.h> #include <asm/assembler.h> #include <asm/smp.h> +#include <asm/unwind_hints.h> .text /* @@ -99,6 +100,7 @@ SYM_FUNC_END(__cpu_suspend_enter) .pushsection ".idmap.text", "awx" SYM_CODE_START(cpu_resume) + UNWIND_HINT_EMPTY bl init_kernel_el bl switch_to_vhe bl __cpu_setup @@ -112,6 +114,7 @@ SYM_CODE_END(cpu_resume) .popsection SYM_CODE_START(_cpu_resume) + UNWIND_HINT_EMPTY mrs x1, mpidr_el1 adr_l x8, mpidr_hash // x8 = struct mpidr_hash virt address diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S index 7839d075729b..4a65262a4f3a 100644 --- a/arch/arm64/kvm/hyp/hyp-entry.S +++ b/arch/arm64/kvm/hyp/hyp-entry.S @@ -14,6 +14,7 @@ #include <asm/kvm_asm.h> #include <asm/mmu.h> #include <asm/spectre.h> +#include <asm/unwind_hints.h> .macro save_caller_saved_regs_vect /* x0 and x1 were saved in the vector entry */ diff --git a/arch/arm64/mm/trans_pgd-asm.S b/arch/arm64/mm/trans_pgd-asm.S index 021c31573bcb..148435248860 100644 --- a/arch/arm64/mm/trans_pgd-asm.S +++ b/arch/arm64/mm/trans_pgd-asm.S @@ -8,10 +8,12 @@ #include <linux/linkage.h> #include <asm/assembler.h> #include <asm/kvm_asm.h> +#include <asm/unwind_hints.h> .macro invalid_vector label SYM_CODE_START_LOCAL(\label) .align 7 + UNWIND_HINT_EMPTY b \label SYM_CODE_END(\label) .endm @@ -19,6 +21,7 @@ SYM_CODE_END(\label) .macro el1_sync_vector SYM_CODE_START_LOCAL(el1_sync) .align 7 + UNWIND_HINT_EMPTY cmp x0, #HVC_SET_VECTORS /* Called from hibernate */ b.ne 1f msr vbar_el2, x1 -- 2.17.1
