* [PATCH 1/4] arm64: consistently log ESR and page table
2017-10-19 15:55 [PATCH 0/4] arm64: Changes to register and stack dumps Will Deacon
@ 2017-10-19 15:55 ` Will Deacon
2017-10-19 15:55 ` [PATCH 2/4] arm64: traps: Don't print stack or raw PC/LR values in backtraces Will Deacon
` (3 subsequent siblings)
4 siblings, 0 replies; 10+ messages in thread
From: Will Deacon @ 2017-10-19 15:55 UTC (permalink / raw)
To: linux-arm-kernel
From: Mark Rutland <mark.rutland@arm.com>
When we take a fault we can't handle, we try to dump some relevant
information, but we're not consistent about doing so.
In do_mem_abort(), we log the full ESR, but don't dump a page table
walk. In __do_kernel_fault, we dump an attempted decoding of the ESR
(but not the ESR itself) along with a page table walk.
Let's try to make things more consistent by dumping the full ESR in
mem_abort_decode(), and having do_mem_abort dump a page table walk. The
existing dump of the ESR in do_mem_abort() is rendered redundant, and
removed.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Julien Thierry <julien.thierry@arm.com>
Cc: Kristina Martsenko <kristina.martsenko@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
arch/arm64/mm/fault.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 02d92bdf1c49..eec09c623d8e 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -112,6 +112,7 @@ static void mem_abort_decode(unsigned int esr)
{
pr_alert("Mem abort info:\n");
+ pr_alert(" ESR = 0x%08x\n", esr);
pr_alert(" Exception class = %s, IL = %u bits\n",
esr_get_class_string(esr),
(esr & ESR_ELx_IL) ? 32 : 16);
@@ -745,11 +746,13 @@ asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
if (!inf->fn(addr, esr, regs))
return;
- pr_alert("Unhandled fault: %s (0x%08x) at 0x%016lx\n",
- inf->name, esr, addr);
+ pr_alert("Unhandled fault: %s at 0x%016lx\n",
+ inf->name, addr);
mem_abort_decode(esr);
+ show_pte(addr);
+
info.si_signo = inf->sig;
info.si_errno = 0;
info.si_code = inf->code;
--
2.1.4
^ permalink raw reply related [flat|nested] 10+ messages in thread* [PATCH 2/4] arm64: traps: Don't print stack or raw PC/LR values in backtraces
2017-10-19 15:55 [PATCH 0/4] arm64: Changes to register and stack dumps Will Deacon
2017-10-19 15:55 ` [PATCH 1/4] arm64: consistently log ESR and page table Will Deacon
@ 2017-10-19 15:55 ` Will Deacon
2017-10-19 15:55 ` [PATCH 3/4] arm64: traps: Pretty-print pstate in register dumps Will Deacon
` (2 subsequent siblings)
4 siblings, 0 replies; 10+ messages in thread
From: Will Deacon @ 2017-10-19 15:55 UTC (permalink / raw)
To: linux-arm-kernel
Printing raw pointer values in backtraces has potential security
implications and are of questionable value anyway.
This patch follows x86's lead and removes the "Exception stack:" dump
from kernel backtraces, as well as converting PC/LR values to symbols
such as "sysrq_handle_crash+0x20/0x30".
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
arch/arm64/kernel/process.c | 8 +++---
arch/arm64/kernel/traps.c | 65 +++------------------------------------------
2 files changed, 6 insertions(+), 67 deletions(-)
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index 2dc0f8482210..c20896b8fb2d 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -186,11 +186,9 @@ void __show_regs(struct pt_regs *regs)
}
show_regs_print_info(KERN_DEFAULT);
- print_symbol("PC is at %s\n", instruction_pointer(regs));
- print_symbol("LR is at %s\n", lr);
- printk("pc : [<%016llx>] lr : [<%016llx>] pstate: %08llx\n",
- regs->pc, lr, regs->pstate);
- printk("sp : %016llx\n", sp);
+ print_symbol("pc : %s\n", regs->pc);
+ print_symbol("lr : %s\n", lr);
+ printk("sp : %016llx pstate : %08llx\n", sp, regs->pstate);
i = top_reg;
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 5ea4b85aee0e..57794773863c 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -58,55 +58,9 @@ static const char *handler[]= {
int show_unhandled_signals = 1;
-/*
- * Dump out the contents of some kernel memory nicely...
- */
-static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
- unsigned long top)
-{
- unsigned long first;
- mm_segment_t fs;
- int i;
-
- /*
- * We need to switch to kernel mode so that we can use __get_user
- * to safely read from kernel space.
- */
- fs = get_fs();
- set_fs(KERNEL_DS);
-
- printk("%s%s(0x%016lx to 0x%016lx)\n", lvl, str, bottom, top);
-
- for (first = bottom & ~31; first < top; first += 32) {
- unsigned long p;
- char str[sizeof(" 12345678") * 8 + 1];
-
- memset(str, ' ', sizeof(str));
- str[sizeof(str) - 1] = '\0';
-
- for (p = first, i = 0; i < (32 / 8)
- && p < top; i++, p += 8) {
- if (p >= bottom && p < top) {
- unsigned long val;
-
- if (__get_user(val, (unsigned long *)p) == 0)
- sprintf(str + i * 17, " %016lx", val);
- else
- sprintf(str + i * 17, " ????????????????");
- }
- }
- printk("%s%04lx:%s\n", lvl, first & 0xffff, str);
- }
-
- set_fs(fs);
-}
-
static void dump_backtrace_entry(unsigned long where)
{
- /*
- * Note that 'where' can have a physical address, but it's not handled.
- */
- print_ip_sym(where);
+ printk(" %pS\n", (void *)where);
}
static void __dump_instr(const char *lvl, struct pt_regs *regs)
@@ -171,10 +125,7 @@ void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
skip = !!regs;
printk("Call trace:\n");
- while (1) {
- unsigned long stack;
- int ret;
-
+ do {
/* skip until specified stack frame */
if (!skip) {
dump_backtrace_entry(frame.pc);
@@ -189,17 +140,7 @@ void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
*/
dump_backtrace_entry(regs->pc);
}
- ret = unwind_frame(tsk, &frame);
- if (ret < 0)
- break;
- if (in_entry_text(frame.pc)) {
- stack = frame.fp - offsetof(struct pt_regs, stackframe);
-
- if (on_accessible_stack(tsk, stack))
- dump_mem("", "Exception stack", stack,
- stack + sizeof(struct pt_regs));
- }
- }
+ } while (!unwind_frame(tsk, &frame));
put_task_stack(tsk);
}
--
2.1.4
^ permalink raw reply related [flat|nested] 10+ messages in thread* [PATCH 3/4] arm64: traps: Pretty-print pstate in register dumps
2017-10-19 15:55 [PATCH 0/4] arm64: Changes to register and stack dumps Will Deacon
2017-10-19 15:55 ` [PATCH 1/4] arm64: consistently log ESR and page table Will Deacon
2017-10-19 15:55 ` [PATCH 2/4] arm64: traps: Don't print stack or raw PC/LR values in backtraces Will Deacon
@ 2017-10-19 15:55 ` Will Deacon
2017-10-19 16:17 ` Mark Rutland
2017-10-19 15:55 ` [PATCH 4/4] arm64: uapi: Remove PSR_Q_BIT Will Deacon
2017-10-20 22:53 ` [PATCH 0/4] arm64: Changes to register and stack dumps Laura Abbott
4 siblings, 1 reply; 10+ messages in thread
From: Will Deacon @ 2017-10-19 15:55 UTC (permalink / raw)
To: linux-arm-kernel
We can decode the PSTATE easily enough, so pretty-print it in register
dumps.
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
arch/arm64/kernel/process.c | 20 +++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index c20896b8fb2d..be3cf9cd7dec 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -170,6 +170,23 @@ void machine_restart(char *cmd)
while (1);
}
+static void print_pstate(struct pt_regs *regs)
+{
+ u64 pstate = regs->pstate;
+ printk("pstate: %08llx (%c%c%c%c %c%c%c%c %cPAN %cUAO)\n",
+ pstate,
+ pstate & PSR_N_BIT ? 'N' : 'n',
+ pstate & PSR_Z_BIT ? 'Z' : 'z',
+ pstate & PSR_C_BIT ? 'C' : 'c',
+ pstate & PSR_V_BIT ? 'V' : 'v',
+ pstate & PSR_D_BIT ? 'D' : 'd',
+ pstate & PSR_A_BIT ? 'A' : 'a',
+ pstate & PSR_I_BIT ? 'I' : 'i',
+ pstate & PSR_F_BIT ? 'F' : 'f',
+ pstate & PSR_PAN_BIT ? '+' : '-',
+ pstate & PSR_UAO_BIT ? '+' : '-');
+}
+
void __show_regs(struct pt_regs *regs)
{
int i, top_reg;
@@ -186,9 +203,10 @@ void __show_regs(struct pt_regs *regs)
}
show_regs_print_info(KERN_DEFAULT);
+ print_pstate(regs);
print_symbol("pc : %s\n", regs->pc);
print_symbol("lr : %s\n", lr);
- printk("sp : %016llx pstate : %08llx\n", sp, regs->pstate);
+ printk("sp : %016llx\n", sp);
i = top_reg;
--
2.1.4
^ permalink raw reply related [flat|nested] 10+ messages in thread* [PATCH 3/4] arm64: traps: Pretty-print pstate in register dumps
2017-10-19 15:55 ` [PATCH 3/4] arm64: traps: Pretty-print pstate in register dumps Will Deacon
@ 2017-10-19 16:17 ` Mark Rutland
2017-10-20 15:58 ` Will Deacon
0 siblings, 1 reply; 10+ messages in thread
From: Mark Rutland @ 2017-10-19 16:17 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Oct 19, 2017 at 04:55:33PM +0100, Will Deacon wrote:
> We can decode the PSTATE easily enough, so pretty-print it in register
> dumps.
>
> Signed-off-by: Will Deacon <will.deacon@arm.com>
> ---
> arch/arm64/kernel/process.c | 20 +++++++++++++++++++-
> 1 file changed, 19 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
> index c20896b8fb2d..be3cf9cd7dec 100644
> --- a/arch/arm64/kernel/process.c
> +++ b/arch/arm64/kernel/process.c
> @@ -170,6 +170,23 @@ void machine_restart(char *cmd)
> while (1);
> }
>
> +static void print_pstate(struct pt_regs *regs)
> +{
> + u64 pstate = regs->pstate;
> + printk("pstate: %08llx (%c%c%c%c %c%c%c%c %cPAN %cUAO)\n",
> + pstate,
> + pstate & PSR_N_BIT ? 'N' : 'n',
> + pstate & PSR_Z_BIT ? 'Z' : 'z',
> + pstate & PSR_C_BIT ? 'C' : 'c',
> + pstate & PSR_V_BIT ? 'V' : 'v',
> + pstate & PSR_D_BIT ? 'D' : 'd',
> + pstate & PSR_A_BIT ? 'A' : 'a',
> + pstate & PSR_I_BIT ? 'I' : 'i',
> + pstate & PSR_F_BIT ? 'F' : 'f',
> + pstate & PSR_PAN_BIT ? '+' : '-',
> + pstate & PSR_UAO_BIT ? '+' : '-');
> +}
Given we use __show_regs for user state, I think we need to check
compat_user_mode() regs, and adjust the decoding accordingly.
e.g. AArch32 has an E bit where the D in DAIF is.
Thanks,
Mark.
> +
> void __show_regs(struct pt_regs *regs)
> {
> int i, top_reg;
> @@ -186,9 +203,10 @@ void __show_regs(struct pt_regs *regs)
> }
>
> show_regs_print_info(KERN_DEFAULT);
> + print_pstate(regs);
> print_symbol("pc : %s\n", regs->pc);
> print_symbol("lr : %s\n", lr);
> - printk("sp : %016llx pstate : %08llx\n", sp, regs->pstate);
> + printk("sp : %016llx\n", sp);
>
> i = top_reg;
>
> --
> 2.1.4
>
^ permalink raw reply [flat|nested] 10+ messages in thread* [PATCH 3/4] arm64: traps: Pretty-print pstate in register dumps
2017-10-19 16:17 ` Mark Rutland
@ 2017-10-20 15:58 ` Will Deacon
2017-10-20 16:08 ` Mark Rutland
0 siblings, 1 reply; 10+ messages in thread
From: Will Deacon @ 2017-10-20 15:58 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Oct 19, 2017 at 05:17:55PM +0100, Mark Rutland wrote:
> On Thu, Oct 19, 2017 at 04:55:33PM +0100, Will Deacon wrote:
> > We can decode the PSTATE easily enough, so pretty-print it in register
> > dumps.
> >
> > Signed-off-by: Will Deacon <will.deacon@arm.com>
> > ---
> > arch/arm64/kernel/process.c | 20 +++++++++++++++++++-
> > 1 file changed, 19 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
> > index c20896b8fb2d..be3cf9cd7dec 100644
> > --- a/arch/arm64/kernel/process.c
> > +++ b/arch/arm64/kernel/process.c
> > @@ -170,6 +170,23 @@ void machine_restart(char *cmd)
> > while (1);
> > }
> >
> > +static void print_pstate(struct pt_regs *regs)
> > +{
> > + u64 pstate = regs->pstate;
> > + printk("pstate: %08llx (%c%c%c%c %c%c%c%c %cPAN %cUAO)\n",
> > + pstate,
> > + pstate & PSR_N_BIT ? 'N' : 'n',
> > + pstate & PSR_Z_BIT ? 'Z' : 'z',
> > + pstate & PSR_C_BIT ? 'C' : 'c',
> > + pstate & PSR_V_BIT ? 'V' : 'v',
> > + pstate & PSR_D_BIT ? 'D' : 'd',
> > + pstate & PSR_A_BIT ? 'A' : 'a',
> > + pstate & PSR_I_BIT ? 'I' : 'i',
> > + pstate & PSR_F_BIT ? 'F' : 'f',
> > + pstate & PSR_PAN_BIT ? '+' : '-',
> > + pstate & PSR_UAO_BIT ? '+' : '-');
> > +}
>
> Given we use __show_regs for user state, I think we need to check
> compat_user_mode() regs, and adjust the decoding accordingly.
>
> e.g. AArch32 has an E bit where the D in DAIF is.
Yes, you're right. There's lots of exciting bits in the AArch32 pstate
too. I ended up with the diff below.
Will
--->8
+static void print_pstate(struct pt_regs *regs)
+{
+ u64 pstate = regs->pstate;
+
+ if (compat_user_mode(regs))
+ printk("pstate: %08llx (%c%c%c%c %c %s %s-endian %c%c%c)\n",
+ pstate,
+ pstate & COMPAT_PSR_N_BIT ? 'N' : 'n',
+ pstate & COMPAT_PSR_Z_BIT ? 'Z' : 'z',
+ pstate & COMPAT_PSR_C_BIT ? 'C' : 'c',
+ pstate & COMPAT_PSR_V_BIT ? 'V' : 'v',
+ pstate & COMPAT_PSR_Q_BIT ? 'Q' : 'q',
+ pstate & COMPAT_PSR_T_BIT ? "T32" : "A32",
+ pstate & COMPAT_PSR_E_BIT ? "big" : "little",
+ pstate & COMPAT_PSR_A_BIT ? 'A' : 'a',
+ pstate & COMPAT_PSR_I_BIT ? 'I' : 'i',
+ pstate & COMPAT_PSR_F_BIT ? 'F' : 'f');
+ else
+ printk("pstate: %08llx (%c%c%c%c %c%c%c%c %cPAN %cUAO)\n",
+ pstate,
+ pstate & PSR_N_BIT ? 'N' : 'n',
+ pstate & PSR_Z_BIT ? 'Z' : 'z',
+ pstate & PSR_C_BIT ? 'C' : 'c',
+ pstate & PSR_V_BIT ? 'V' : 'v',
+ pstate & PSR_D_BIT ? 'D' : 'd',
+ pstate & PSR_A_BIT ? 'A' : 'a',
+ pstate & PSR_I_BIT ? 'I' : 'i',
+ pstate & PSR_F_BIT ? 'F' : 'f',
+ pstate & PSR_PAN_BIT ? '+' : '-',
+ pstate & PSR_UAO_BIT ? '+' : '-');
+}
^ permalink raw reply [flat|nested] 10+ messages in thread* [PATCH 3/4] arm64: traps: Pretty-print pstate in register dumps
2017-10-20 15:58 ` Will Deacon
@ 2017-10-20 16:08 ` Mark Rutland
0 siblings, 0 replies; 10+ messages in thread
From: Mark Rutland @ 2017-10-20 16:08 UTC (permalink / raw)
To: linux-arm-kernel
On Fri, Oct 20, 2017 at 04:58:37PM +0100, Will Deacon wrote:
> On Thu, Oct 19, 2017 at 05:17:55PM +0100, Mark Rutland wrote:
> > On Thu, Oct 19, 2017 at 04:55:33PM +0100, Will Deacon wrote:
> > > We can decode the PSTATE easily enough, so pretty-print it in register
> > > dumps.
> > >
> > > Signed-off-by: Will Deacon <will.deacon@arm.com>
> > > ---
> > > arch/arm64/kernel/process.c | 20 +++++++++++++++++++-
> > > 1 file changed, 19 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
> > > index c20896b8fb2d..be3cf9cd7dec 100644
> > > --- a/arch/arm64/kernel/process.c
> > > +++ b/arch/arm64/kernel/process.c
> > > @@ -170,6 +170,23 @@ void machine_restart(char *cmd)
> > > while (1);
> > > }
> > >
> > > +static void print_pstate(struct pt_regs *regs)
> > > +{
> > > + u64 pstate = regs->pstate;
> > > + printk("pstate: %08llx (%c%c%c%c %c%c%c%c %cPAN %cUAO)\n",
> > > + pstate,
> > > + pstate & PSR_N_BIT ? 'N' : 'n',
> > > + pstate & PSR_Z_BIT ? 'Z' : 'z',
> > > + pstate & PSR_C_BIT ? 'C' : 'c',
> > > + pstate & PSR_V_BIT ? 'V' : 'v',
> > > + pstate & PSR_D_BIT ? 'D' : 'd',
> > > + pstate & PSR_A_BIT ? 'A' : 'a',
> > > + pstate & PSR_I_BIT ? 'I' : 'i',
> > > + pstate & PSR_F_BIT ? 'F' : 'f',
> > > + pstate & PSR_PAN_BIT ? '+' : '-',
> > > + pstate & PSR_UAO_BIT ? '+' : '-');
> > > +}
> >
> > Given we use __show_regs for user state, I think we need to check
> > compat_user_mode() regs, and adjust the decoding accordingly.
> >
> > e.g. AArch32 has an E bit where the D in DAIF is.
>
> Yes, you're right. There's lots of exciting bits in the AArch32 pstate
> too. I ended up with the diff below.
>
> Will
>
> --->8
>
> +static void print_pstate(struct pt_regs *regs)
> +{
> + u64 pstate = regs->pstate;
> +
> + if (compat_user_mode(regs))
> + printk("pstate: %08llx (%c%c%c%c %c %s %s-endian %c%c%c)\n",
> + pstate,
> + pstate & COMPAT_PSR_N_BIT ? 'N' : 'n',
> + pstate & COMPAT_PSR_Z_BIT ? 'Z' : 'z',
> + pstate & COMPAT_PSR_C_BIT ? 'C' : 'c',
> + pstate & COMPAT_PSR_V_BIT ? 'V' : 'v',
> + pstate & COMPAT_PSR_Q_BIT ? 'Q' : 'q',
> + pstate & COMPAT_PSR_T_BIT ? "T32" : "A32",
> + pstate & COMPAT_PSR_E_BIT ? "big" : "little",
We could say BE/LE for these so as to keep the line short.
> + pstate & COMPAT_PSR_A_BIT ? 'A' : 'a',
> + pstate & COMPAT_PSR_I_BIT ? 'I' : 'i',
> + pstate & COMPAT_PSR_F_BIT ? 'F' : 'f');
> + else
Given the either side of the if-else is several lines, could we add
braces for clarity?
> + printk("pstate: %08llx (%c%c%c%c %c%c%c%c %cPAN %cUAO)\n",
> + pstate,
> + pstate & PSR_N_BIT ? 'N' : 'n',
> + pstate & PSR_Z_BIT ? 'Z' : 'z',
> + pstate & PSR_C_BIT ? 'C' : 'c',
> + pstate & PSR_V_BIT ? 'V' : 'v',
> + pstate & PSR_D_BIT ? 'D' : 'd',
> + pstate & PSR_A_BIT ? 'A' : 'a',
> + pstate & PSR_I_BIT ? 'I' : 'i',
> + pstate & PSR_F_BIT ? 'F' : 'f',
> + pstate & PSR_PAN_BIT ? '+' : '-',
> + pstate & PSR_UAO_BIT ? '+' : '-');
> +}
Otherwise, looks good!
Thanks,
Mark.
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH 4/4] arm64: uapi: Remove PSR_Q_BIT
2017-10-19 15:55 [PATCH 0/4] arm64: Changes to register and stack dumps Will Deacon
` (2 preceding siblings ...)
2017-10-19 15:55 ` [PATCH 3/4] arm64: traps: Pretty-print pstate in register dumps Will Deacon
@ 2017-10-19 15:55 ` Will Deacon
2017-10-20 22:53 ` [PATCH 0/4] arm64: Changes to register and stack dumps Laura Abbott
4 siblings, 0 replies; 10+ messages in thread
From: Will Deacon @ 2017-10-19 15:55 UTC (permalink / raw)
To: linux-arm-kernel
PSTATE.Q only exists for AArch32, which can be referred to using
COMPAT_PSR_Q_BIT. Remove PSR_Q_BIT, since the native bit doesn't exist
in the architecture
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
arch/arm64/include/uapi/asm/ptrace.h | 1 -
1 file changed, 1 deletion(-)
diff --git a/arch/arm64/include/uapi/asm/ptrace.h b/arch/arm64/include/uapi/asm/ptrace.h
index d1ff83dfe5de..3697d95ba0a1 100644
--- a/arch/arm64/include/uapi/asm/ptrace.h
+++ b/arch/arm64/include/uapi/asm/ptrace.h
@@ -46,7 +46,6 @@
#define PSR_D_BIT 0x00000200
#define PSR_PAN_BIT 0x00400000
#define PSR_UAO_BIT 0x00800000
-#define PSR_Q_BIT 0x08000000
#define PSR_V_BIT 0x10000000
#define PSR_C_BIT 0x20000000
#define PSR_Z_BIT 0x40000000
--
2.1.4
^ permalink raw reply related [flat|nested] 10+ messages in thread* [PATCH 0/4] arm64: Changes to register and stack dumps
2017-10-19 15:55 [PATCH 0/4] arm64: Changes to register and stack dumps Will Deacon
` (3 preceding siblings ...)
2017-10-19 15:55 ` [PATCH 4/4] arm64: uapi: Remove PSR_Q_BIT Will Deacon
@ 2017-10-20 22:53 ` Laura Abbott
2017-10-23 9:03 ` Will Deacon
4 siblings, 1 reply; 10+ messages in thread
From: Laura Abbott @ 2017-10-20 22:53 UTC (permalink / raw)
To: linux-arm-kernel
On 10/19/2017 08:55 AM, Will Deacon wrote:
> Hi all,
>
> This handful of patches makes some significant changes to how we print
> register/stack dumps and brings us inline with recent changes to x86.
> The main changes are that we no longer print out the 'Exception stack:'
> section and PC/LR values are resolved to a symbol+offset format where
> possible.
>
> Feedback welcome.
>
In very petty complaints, I can no longer just use the PC/LR with
addr2line. Yes I can use gdb or one of the scripts but that's a
few more steps when I'm doing debugging on my own. Like I said,
very minor and overall this is good for both security and alignment.
I ran this through several of the LKDTM tests and the backtraces
looked fine. You're welcome to add
Tested-by: Laura Abbott <labbott@redhat.com>
> Will
>
> --->8
>
> Mark Rutland (1):
> arm64: consistently log ESR and page table
>
> Will Deacon (3):
> arm64: traps: Don't print stack or raw PC/LR values in backtraces
> arm64: traps: Pretty-print pstate in register dumps
> arm64: uapi: Remove PSR_Q_BIT
>
> arch/arm64/include/uapi/asm/ptrace.h | 1 -
> arch/arm64/kernel/process.c | 24 ++++++++++---
> arch/arm64/kernel/traps.c | 65 ++----------------------------------
> arch/arm64/mm/fault.c | 7 ++--
> 4 files changed, 28 insertions(+), 69 deletions(-)
>
^ permalink raw reply [flat|nested] 10+ messages in thread* [PATCH 0/4] arm64: Changes to register and stack dumps
2017-10-20 22:53 ` [PATCH 0/4] arm64: Changes to register and stack dumps Laura Abbott
@ 2017-10-23 9:03 ` Will Deacon
0 siblings, 0 replies; 10+ messages in thread
From: Will Deacon @ 2017-10-23 9:03 UTC (permalink / raw)
To: linux-arm-kernel
On Fri, Oct 20, 2017 at 03:53:50PM -0700, Laura Abbott wrote:
> On 10/19/2017 08:55 AM, Will Deacon wrote:
> > This handful of patches makes some significant changes to how we print
> > register/stack dumps and brings us inline with recent changes to x86.
> > The main changes are that we no longer print out the 'Exception stack:'
> > section and PC/LR values are resolved to a symbol+offset format where
> > possible.
> >
> > Feedback welcome.
> >
>
> In very petty complaints, I can no longer just use the PC/LR with
> addr2line. Yes I can use gdb or one of the scripts but that's a
> few more steps when I'm doing debugging on my own. Like I said,
> very minor and overall this is good for both security and alignment.
Understood. scripts/faddr2line seems to do a reasonable job, but I agree
that it's a little annoying that you have to do some pointer arithmetic
if you want to e.g. locate disassembly in objdump. Setting KALLSYMS=n will
give you the addresses if you *really* want them.
> I ran this through several of the LKDTM tests and the backtraces
> looked fine. You're welcome to add
>
> Tested-by: Laura Abbott <labbott@redhat.com>
Thanks, Laura.
Will
^ permalink raw reply [flat|nested] 10+ messages in thread