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authorMarcel Ziswiler <marcel.ziswiler@toradex.com>2017-04-04 14:23:55 +0200
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2017-04-04 14:23:55 +0200
commit837e5b8e0685e2e4974e5a86dfd7cbf5802e1422 (patch)
tree1b4e116a20e6fdef01a1fc9ee7b46aeeecc23ed0 /arch/arm/kernel
parent418f717cce5834203e24368717f542360b020681 (diff)
parent61a4577c9a4419b99e647744923517d47255da35 (diff)
Merge tag 'v4.4.59' into toradex_vf_4.4-next
This is the 4.4.59 stable release
Diffstat (limited to 'arch/arm/kernel')
-rw-r--r--arch/arm/kernel/hw_breakpoint.c16
-rw-r--r--arch/arm/kernel/ptrace.c2
-rw-r--r--arch/arm/kernel/smp_tlb.c7
3 files changed, 24 insertions, 1 deletions
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index 6284779d64ee..abcbea1ae30b 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -1066,6 +1066,22 @@ static int __init arch_hw_breakpoint_init(void)
return 0;
}
+ /*
+ * Scorpion CPUs (at least those in APQ8060) seem to set DBGPRSR.SPD
+ * whenever a WFI is issued, even if the core is not powered down, in
+ * violation of the architecture. When DBGPRSR.SPD is set, accesses to
+ * breakpoint and watchpoint registers are treated as undefined, so
+ * this results in boot time and runtime failures when these are
+ * accessed and we unexpectedly take a trap.
+ *
+ * It's not clear if/how this can be worked around, so we blacklist
+ * Scorpion CPUs to avoid these issues.
+ */
+ if (read_cpuid_part() == ARM_CPU_PART_SCORPION) {
+ pr_info("Scorpion CPU detected. Hardware breakpoints and watchpoints disabled\n");
+ return 0;
+ }
+
has_ossr = core_has_os_save_restore();
/* Determine how many BRPs/WRPs are available. */
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 4d9375814b53..d54c53b7ab63 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -600,7 +600,7 @@ static int gpr_set(struct task_struct *target,
const void *kbuf, const void __user *ubuf)
{
int ret;
- struct pt_regs newregs;
+ struct pt_regs newregs = *task_pt_regs(target);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&newregs,
diff --git a/arch/arm/kernel/smp_tlb.c b/arch/arm/kernel/smp_tlb.c
index 2e72be4f623e..7cb079e74010 100644
--- a/arch/arm/kernel/smp_tlb.c
+++ b/arch/arm/kernel/smp_tlb.c
@@ -9,6 +9,7 @@
*/
#include <linux/preempt.h>
#include <linux/smp.h>
+#include <linux/uaccess.h>
#include <asm/smp_plat.h>
#include <asm/tlbflush.h>
@@ -40,8 +41,11 @@ static inline void ipi_flush_tlb_mm(void *arg)
static inline void ipi_flush_tlb_page(void *arg)
{
struct tlb_args *ta = (struct tlb_args *)arg;
+ unsigned int __ua_flags = uaccess_save_and_enable();
local_flush_tlb_page(ta->ta_vma, ta->ta_start);
+
+ uaccess_restore(__ua_flags);
}
static inline void ipi_flush_tlb_kernel_page(void *arg)
@@ -54,8 +58,11 @@ static inline void ipi_flush_tlb_kernel_page(void *arg)
static inline void ipi_flush_tlb_range(void *arg)
{
struct tlb_args *ta = (struct tlb_args *)arg;
+ unsigned int __ua_flags = uaccess_save_and_enable();
local_flush_tlb_range(ta->ta_vma, ta->ta_start, ta->ta_end);
+
+ uaccess_restore(__ua_flags);
}
static inline void ipi_flush_tlb_kernel_range(void *arg)