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authorLinus Torvalds <torvalds@linux-foundation.org>2020-08-03 14:11:08 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-03 14:11:08 -0700
commit145ff1ec090dce9beb5a9590b5dc288e7bb2e65d (patch)
tree3e10a7c59553e56c1ea5f0aa71a2c3c9d6b7982b /arch/arm64/kernel/entry.S
parent8c4e1c027ae63c67c523d695e4e8565ff78af1ba (diff)
parent0e4cd9f2654915be8d09a1bd1b405ce5426e64c4 (diff)
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 and cross-arch updates from Catalin Marinas: "Here's a slightly wider-spread set of updates for 5.9. Going outside the usual arch/arm64/ area is the removal of read_barrier_depends() series from Will and the MSI/IOMMU ID translation series from Lorenzo. The notable arm64 updates include ARMv8.4 TLBI range operations and translation level hint, time namespace support, and perf. Summary: - Removal of the tremendously unpopular read_barrier_depends() barrier, which is a NOP on all architectures apart from Alpha, in favour of allowing architectures to override READ_ONCE() and do whatever dance they need to do to ensure address dependencies provide LOAD -> LOAD/STORE ordering. This work also offers a potential solution if compilers are shown to convert LOAD -> LOAD address dependencies into control dependencies (e.g. under LTO), as weakly ordered architectures will effectively be able to upgrade READ_ONCE() to smp_load_acquire(). The latter case is not used yet, but will be discussed further at LPC. - Make the MSI/IOMMU input/output ID translation PCI agnostic, augment the MSI/IOMMU ACPI/OF ID mapping APIs to accept an input ID bus-specific parameter and apply the resulting changes to the device ID space provided by the Freescale FSL bus. - arm64 support for TLBI range operations and translation table level hints (part of the ARMv8.4 architecture version). - Time namespace support for arm64. - Export the virtual and physical address sizes in vmcoreinfo for makedumpfile and crash utilities. - CPU feature handling cleanups and checks for programmer errors (overlapping bit-fields). - ACPI updates for arm64: disallow AML accesses to EFI code regions and kernel memory. - perf updates for arm64. - Miscellaneous fixes and cleanups, most notably PLT counting optimisation for module loading, recordmcount fix to ignore relocations other than R_AARCH64_CALL26, CMA areas reserved for gigantic pages on 16K and 64K configurations. - Trivial typos, duplicate words" Link: http://lkml.kernel.org/r/20200710165203.31284-1-will@kernel.org Link: http://lkml.kernel.org/r/20200619082013.13661-1-lorenzo.pieralisi@arm.com * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (82 commits) arm64: use IRQ_STACK_SIZE instead of THREAD_SIZE for irq stack arm64/mm: save memory access in check_and_switch_context() fast switch path arm64: sigcontext.h: delete duplicated word arm64: ptrace.h: delete duplicated word arm64: pgtable-hwdef.h: delete duplicated words bus: fsl-mc: Add ACPI support for fsl-mc bus/fsl-mc: Refactor the MSI domain creation in the DPRC driver of/irq: Make of_msi_map_rid() PCI bus agnostic of/irq: make of_msi_map_get_device_domain() bus agnostic dt-bindings: arm: fsl: Add msi-map device-tree binding for fsl-mc bus of/device: Add input id to of_dma_configure() of/iommu: Make of_map_rid() PCI agnostic ACPI/IORT: Add an input ID to acpi_dma_configure() ACPI/IORT: Remove useless PCI bus walk ACPI/IORT: Make iort_msi_map_rid() PCI agnostic ACPI/IORT: Make iort_get_device_domain IRQ domain agnostic ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC arm64: enable time namespace support arm64/vdso: Restrict splitting VVAR VMA arm64/vdso: Handle faults on timens page ...
Diffstat (limited to 'arch/arm64/kernel/entry.S')
-rw-r--r--arch/arm64/kernel/entry.S96
1 files changed, 48 insertions, 48 deletions
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 35de8ba60e3d..2646178c8329 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -15,6 +15,7 @@
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/asm_pointer_auth.h>
+#include <asm/bug.h>
#include <asm/cpufeature.h>
#include <asm/errno.h>
#include <asm/esr.h>
@@ -226,28 +227,9 @@ alternative_else_nop_endif
add x29, sp, #S_STACKFRAME
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
- /*
- * Set the TTBR0 PAN bit in SPSR. When the exception is taken from
- * EL0, there is no need to check the state of TTBR0_EL1 since
- * accesses are always enabled.
- * Note that the meaning of this bit differs from the ARMv8.1 PAN
- * feature as all TTBR0_EL1 accesses are disabled, not just those to
- * user mappings.
- */
-alternative_if ARM64_HAS_PAN
- b 1f // skip TTBR0 PAN
+alternative_if_not ARM64_HAS_PAN
+ bl __swpan_entry_el\el
alternative_else_nop_endif
-
- .if \el != 0
- mrs x21, ttbr0_el1
- tst x21, #TTBR_ASID_MASK // Check for the reserved ASID
- orr x23, x23, #PSR_PAN_BIT // Set the emulated PAN in the saved SPSR
- b.eq 1f // TTBR0 access already disabled
- and x23, x23, #~PSR_PAN_BIT // Clear the emulated PAN in the saved SPSR
- .endif
-
- __uaccess_ttbr0_disable x21
-1:
#endif
stp x22, x23, [sp, #S_PC]
@@ -301,34 +283,9 @@ alternative_else_nop_endif
.endif
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
- /*
- * Restore access to TTBR0_EL1. If returning to EL0, no need for SPSR
- * PAN bit checking.
- */
-alternative_if ARM64_HAS_PAN
- b 2f // skip TTBR0 PAN
+alternative_if_not ARM64_HAS_PAN
+ bl __swpan_exit_el\el
alternative_else_nop_endif
-
- .if \el != 0
- tbnz x22, #22, 1f // Skip re-enabling TTBR0 access if the PSR_PAN_BIT is set
- .endif
-
- __uaccess_ttbr0_enable x0, x1
-
- .if \el == 0
- /*
- * Enable errata workarounds only if returning to user. The only
- * workaround currently required for TTBR0_EL1 changes are for the
- * Cavium erratum 27456 (broadcast TLBI instructions may cause I-cache
- * corruption).
- */
- bl post_ttbr_update_workaround
- .endif
-1:
- .if \el != 0
- and x22, x22, #~PSR_PAN_BIT // ARMv8.0 CPUs do not understand this bit
- .endif
-2:
#endif
.if \el == 0
@@ -401,6 +358,49 @@ alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0
sb
.endm
+#ifdef CONFIG_ARM64_SW_TTBR0_PAN
+ /*
+ * Set the TTBR0 PAN bit in SPSR. When the exception is taken from
+ * EL0, there is no need to check the state of TTBR0_EL1 since
+ * accesses are always enabled.
+ * Note that the meaning of this bit differs from the ARMv8.1 PAN
+ * feature as all TTBR0_EL1 accesses are disabled, not just those to
+ * user mappings.
+ */
+SYM_CODE_START_LOCAL(__swpan_entry_el1)
+ mrs x21, ttbr0_el1
+ tst x21, #TTBR_ASID_MASK // Check for the reserved ASID
+ orr x23, x23, #PSR_PAN_BIT // Set the emulated PAN in the saved SPSR
+ b.eq 1f // TTBR0 access already disabled
+ and x23, x23, #~PSR_PAN_BIT // Clear the emulated PAN in the saved SPSR
+SYM_INNER_LABEL(__swpan_entry_el0, SYM_L_LOCAL)
+ __uaccess_ttbr0_disable x21
+1: ret
+SYM_CODE_END(__swpan_entry_el1)
+
+ /*
+ * Restore access to TTBR0_EL1. If returning to EL0, no need for SPSR
+ * PAN bit checking.
+ */
+SYM_CODE_START_LOCAL(__swpan_exit_el1)
+ tbnz x22, #22, 1f // Skip re-enabling TTBR0 access if the PSR_PAN_BIT is set
+ __uaccess_ttbr0_enable x0, x1
+1: and x22, x22, #~PSR_PAN_BIT // ARMv8.0 CPUs do not understand this bit
+ ret
+SYM_CODE_END(__swpan_exit_el1)
+
+SYM_CODE_START_LOCAL(__swpan_exit_el0)
+ __uaccess_ttbr0_enable x0, x1
+ /*
+ * Enable errata workarounds only if returning to user. The only
+ * workaround currently required for TTBR0_EL1 changes are for the
+ * Cavium erratum 27456 (broadcast TLBI instructions may cause I-cache
+ * corruption).
+ */
+ b post_ttbr_update_workaround
+SYM_CODE_END(__swpan_exit_el0)
+#endif
+
.macro irq_stack_entry
mov x19, sp // preserve the original sp
#ifdef CONFIG_SHADOW_CALL_STACK