arm64: idmap: Use "awx" flags for .idmap.text .pushsection directives

commit 439e70e27a51 upstream.

The identity map is mapped as both writeable and executable by the
SWAPPER_MM_MMUFLAGS and this is relied upon by the kpti code to manage
a synchronisation flag. Update the .pushsection flags to reflect the
actual mapping attributes.

Reported-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Alex Shi <alex.shi@linaro.org> [v4.9 backport]
Signed-off-by: Mark Rutland <mark.rutland@arm.com> [v4.9 backport]
Tested-by: Will Deacon <will.deacon@arm.com>
Tested-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S
index 65f42d2574142d4b37bebf49ed1fc3cdccbb56ae..f736a6f81ecdfab99efad58f3e6f9845851183fc 100644 (file)
--- a/arch/arm64/kernel/cpu-reset.S
+++ b/arch/arm64/kernel/cpu-reset.S
@@ -16,7 +16,7 @@
 #include <asm/virt.h>
 
 .text
-.pushsection    .idmap.text, "ax"
+.pushsection    .idmap.text, "awx"
 
 /*
  * __cpu_soft_restart(el2_switch, entry, arg0, arg1, arg2) - Helper for

diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 539bebc1222f26c7e89ebbbad06404d89eb8d7ff..fa52817d84c5c7c2d0e5a126565aaddc94abe06a 100644 (file)
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -473,7 +473,7 @@ ENDPROC(__primary_switched)
  * end early head section, begin head code that is also used for
  * hotplug and needs to have the same protections as the text region
  */
-       .section ".idmap.text","ax"
+       .section ".idmap.text","awx"
 
 ENTRY(kimage_vaddr)
        .quad           _text - TEXT_OFFSET

diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S
index 1bec41b5fda3917b2ed7583663a239f25c6126bf..0030d6964e653bca1ce4fefb06f346954268e6b1 100644 (file)
--- a/arch/arm64/kernel/sleep.S
+++ b/arch/arm64/kernel/sleep.S
@@ -95,7 +95,7 @@ ENTRY(__cpu_suspend_enter)
        ret
 ENDPROC(__cpu_suspend_enter)
 
-       .pushsection ".idmap.text", "ax"
+       .pushsection ".idmap.text", "awx"
 ENTRY(cpu_resume)
        bl      el2_setup               // if in EL2 drop to EL1 cleanly
        bl      __cpu_setup

diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 5c268f5767b45c7bfe40da77d663a456d60a9778..c07d9cc057e6e8c13a149c3330fcd18c73e9b5ca 100644 (file)
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -83,7 +83,7 @@ ENDPROC(cpu_do_suspend)
  *
  * x0: Address of context pointer
  */
-       .pushsection ".idmap.text", "ax"
+       .pushsection ".idmap.text", "awx"
 ENTRY(cpu_do_resume)
        ldp     x2, x3, [x0]
        ldp     x4, x5, [x0, #16]
@@ -147,7 +147,7 @@ alternative_else_nop_endif
        ret
 ENDPROC(cpu_do_switch_mm)
 
-       .pushsection ".idmap.text", "ax"
+       .pushsection ".idmap.text", "awx"
 
 .macro __idmap_cpu_set_reserved_ttbr1, tmp1, tmp2
        adrp    \tmp1, empty_zero_page
@@ -180,7 +180,7 @@ ENDPROC(idmap_cpu_replace_ttbr1)
        .popsection
 
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-       .pushsection ".idmap.text", "ax"
+       .pushsection ".idmap.text", "awx"
 
        .macro  __idmap_kpti_get_pgtable_ent, type
        dc      cvac, cur_\()\type\()p          // Ensure any existing dirty
@@ -368,7 +368,7 @@ ENDPROC(idmap_kpti_install_ng_mappings)
  *     Initialise the processor for turning the MMU on.  Return in x0 the
  *     value of the SCTLR_EL1 register.
  */
-       .pushsection ".idmap.text", "ax"
+       .pushsection ".idmap.text", "awx"
 ENTRY(__cpu_setup)
        tlbi    vmalle1                         // Invalidate local TLB
        dsb     nsh