This is a note to let you know that I've just added the patch titled arm64: factor out entry stack manipulation to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm64-factor-out-entry-stack-manipulation.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Apr 5 21:39:27 CEST 2018 From: Mark Rutland <mark.rutland@xxxxxxx> Date: Tue, 3 Apr 2018 12:09:02 +0100 Subject: arm64: factor out entry stack manipulation To: stable@xxxxxxxxxxxxxxx Cc: mark.brown@xxxxxxxxxx, ard.biesheuvel@xxxxxxxxxx, marc.zyngier@xxxxxxx, will.deacon@xxxxxxx Message-ID: <20180403110923.43575-7-mark.rutland@xxxxxxx> From: Mark Rutland <mark.rutland@xxxxxxx> commit b11e5759bfac upstream. In subsequent patches, we will detect stack overflow in our exception entry code, by verifying the SP after it has been decremented to make space for the exception regs. This verification code is small, and we can minimize its impact by placing it directly in the vectors. To avoid redundant modification of the SP, we also need to move the initial decrement of the SP into the vectors. As a preparatory step, this patch introduces kernel_ventry, which performs this decrement, and updates the entry code accordingly. Subsequent patches will fold SP verification into kernel_ventry. There should be no functional change as a result of this patch. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> [Mark: turn into prep patch, expand commit msg] Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx> Reviewed-by: Will Deacon <will.deacon@xxxxxxx> Tested-by: Laura Abbott <labbott@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: James Morse <james.morse@xxxxxxx> Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxx> [v4.9 backport] Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx> [v4.9 backport] Tested-by: Will Deacon <will.deacon@xxxxxxx> Tested-by: Greg Hackmann <ghackmann@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/kernel/entry.S | 51 +++++++++++++++++++++++++--------------------- 1 file changed, 28 insertions(+), 23 deletions(-) --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -68,8 +68,13 @@ #define BAD_FIQ 2 #define BAD_ERROR 3 - .macro kernel_entry, el, regsize = 64 + .macro kernel_ventry label + .align 7 sub sp, sp, #S_FRAME_SIZE + b \label + .endm + + .macro kernel_entry, el, regsize = 64 .if \regsize == 32 mov w0, w0 // zero upper 32 bits of x0 .endif @@ -257,31 +262,31 @@ tsk .req x28 // current thread_info .align 11 ENTRY(vectors) - ventry el1_sync_invalid // Synchronous EL1t - ventry el1_irq_invalid // IRQ EL1t - ventry el1_fiq_invalid // FIQ EL1t - ventry el1_error_invalid // Error EL1t - - ventry el1_sync // Synchronous EL1h - ventry el1_irq // IRQ EL1h - ventry el1_fiq_invalid // FIQ EL1h - ventry el1_error_invalid // Error EL1h - - ventry el0_sync // Synchronous 64-bit EL0 - ventry el0_irq // IRQ 64-bit EL0 - ventry el0_fiq_invalid // FIQ 64-bit EL0 - ventry el0_error_invalid // Error 64-bit EL0 + kernel_ventry el1_sync_invalid // Synchronous EL1t + kernel_ventry el1_irq_invalid // IRQ EL1t + kernel_ventry el1_fiq_invalid // FIQ EL1t + kernel_ventry el1_error_invalid // Error EL1t + + kernel_ventry el1_sync // Synchronous EL1h + kernel_ventry el1_irq // IRQ EL1h + kernel_ventry el1_fiq_invalid // FIQ EL1h + kernel_ventry el1_error_invalid // Error EL1h + + kernel_ventry el0_sync // Synchronous 64-bit EL0 + kernel_ventry el0_irq // IRQ 64-bit EL0 + kernel_ventry el0_fiq_invalid // FIQ 64-bit EL0 + kernel_ventry el0_error_invalid // Error 64-bit EL0 #ifdef CONFIG_COMPAT - ventry el0_sync_compat // Synchronous 32-bit EL0 - ventry el0_irq_compat // IRQ 32-bit EL0 - ventry el0_fiq_invalid_compat // FIQ 32-bit EL0 - ventry el0_error_invalid_compat // Error 32-bit EL0 + kernel_ventry el0_sync_compat // Synchronous 32-bit EL0 + kernel_ventry el0_irq_compat // IRQ 32-bit EL0 + kernel_ventry el0_fiq_invalid_compat // FIQ 32-bit EL0 + kernel_ventry el0_error_invalid_compat // Error 32-bit EL0 #else - ventry el0_sync_invalid // Synchronous 32-bit EL0 - ventry el0_irq_invalid // IRQ 32-bit EL0 - ventry el0_fiq_invalid // FIQ 32-bit EL0 - ventry el0_error_invalid // Error 32-bit EL0 + kernel_ventry el0_sync_invalid // Synchronous 32-bit EL0 + kernel_ventry el0_irq_invalid // IRQ 32-bit EL0 + kernel_ventry el0_fiq_invalid // FIQ 32-bit EL0 + kernel_ventry el0_error_invalid // Error 32-bit EL0 #endif END(vectors) Patches currently in stable-queue which might be from mark.rutland@xxxxxxx are queue-4.9/arm64-mm-add-arm64_kernel_unmapped_at_el0-helper.patch queue-4.9/arm64-entry-reword-comment-about-post_ttbr_update_workaround.patch queue-4.9/arm64-kaslr-put-kernel-vectors-address-in-separate-data-page.patch queue-4.9/arm64-turn-on-kpti-only-on-cpus-that-need-it.patch queue-4.9/arm64-force-kpti-to-be-disabled-on-cavium-thunderx.patch queue-4.9/arm64-mm-allocate-asids-in-pairs.patch queue-4.9/arm64-tls-avoid-unconditional-zeroing-of-tpidrro_el0-for-native-tasks.patch queue-4.9/arm64-use-ret-instruction-for-exiting-the-trampoline.patch queue-4.9/arm64-entry-explicitly-pass-exception-level-to-kernel_ventry-macro.patch queue-4.9/arm64-kpti-make-use-of-ng-dependent-on-arm64_kernel_unmapped_at_el0.patch queue-4.9/arm64-mm-use-non-global-mappings-for-kernel-space.patch queue-4.9/arm64-capabilities-handle-duplicate-entries-for-a-capability.patch queue-4.9/arm64-entry-hook-up-entry-trampoline-to-exception-vectors.patch queue-4.9/arm64-mm-invalidate-both-kernel-and-user-asids-when-performing-tlbi.patch queue-4.9/arm64-mm-map-entry-trampoline-into-trampoline-and-kernel-page-tables.patch queue-4.9/module-extend-rodata-off-boot-cmdline-parameter-to-module-mappings.patch queue-4.9/arm64-kconfig-reword-unmap_kernel_at_el0-kconfig-entry.patch queue-4.9/arm64-mm-move-asid-from-ttbr0-to-ttbr1.patch queue-4.9/arm64-allow-checking-of-a-cpu-local-erratum.patch queue-4.9/arm64-take-into-account-id_aa64pfr0_el1.csv3.patch queue-4.9/arm64-kconfig-add-config_unmap_kernel_at_el0.patch queue-4.9/arm64-idmap-use-awx-flags-for-.idmap.text-.pushsection-directives.patch queue-4.9/arm64-factor-out-entry-stack-manipulation.patch queue-4.9/arm64-entry-add-exception-trampoline-page-for-exceptions-from-el0.patch queue-4.9/arm64-kpti-add-enable-callback-to-remap-swapper-using-ng-mappings.patch queue-4.9/arm64-entry-add-fake-cpu-feature-for-unmapping-the-kernel-at-el0.patch queue-4.9/arm64-cputype-add-midr-values-for-cavium-thunderx2-cpus.patch