| Message ID | 20220715061027.1612149-2-kaleshsingh@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM nVHE Hypervisor stack unwinder | expand |
On Thu, Jul 14, 2022 at 11:10:10PM -0700, Kalesh Singh wrote: > In order to reuse the arm64 stack unwinding logic for the nVHE > hypervisor stack, move the common code to a shared header > (arch/arm64/include/asm/stacktrace/common.h). > > The nVHE hypervisor cannot safely link against kernel code, so we > make use of the shared header to avoid duplicated logic later in > this series. Reviewed-by: Mark Brown <broonie@kernel.org>
Hi Kalesh, On Fri, Jul 15, 2022 at 7:10 AM Kalesh Singh <kaleshsingh@google.com> wrote: > > In order to reuse the arm64 stack unwinding logic for the nVHE > hypervisor stack, move the common code to a shared header > (arch/arm64/include/asm/stacktrace/common.h). > > The nVHE hypervisor cannot safely link against kernel code, so we > make use of the shared header to avoid duplicated logic later in > this series. > > Signed-off-by: Kalesh Singh <kaleshsingh@google.com> > --- Reviewed-by: Fuad Tabba <tabba@google.com> Thanks, /fuad > arch/arm64/include/asm/stacktrace.h | 35 +------ > arch/arm64/include/asm/stacktrace/common.h | 105 +++++++++++++++++++++ > arch/arm64/kernel/stacktrace.c | 57 ----------- > 3 files changed, 106 insertions(+), 91 deletions(-) > create mode 100644 arch/arm64/include/asm/stacktrace/common.h > > diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h > index aec9315bf156..79f455b37c84 100644 > --- a/arch/arm64/include/asm/stacktrace.h > +++ b/arch/arm64/include/asm/stacktrace.h > @@ -8,52 +8,19 @@ > #include <linux/percpu.h> > #include <linux/sched.h> > #include <linux/sched/task_stack.h> > -#include <linux/types.h> > #include <linux/llist.h> > > #include <asm/memory.h> > #include <asm/ptrace.h> > #include <asm/sdei.h> > > -enum stack_type { > - STACK_TYPE_UNKNOWN, > - STACK_TYPE_TASK, > - STACK_TYPE_IRQ, > - STACK_TYPE_OVERFLOW, > - STACK_TYPE_SDEI_NORMAL, > - STACK_TYPE_SDEI_CRITICAL, > - __NR_STACK_TYPES > -}; > - > -struct stack_info { > - unsigned long low; > - unsigned long high; > - enum stack_type type; > -}; > +#include <asm/stacktrace/common.h> > > extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, > const char *loglvl); > > DECLARE_PER_CPU(unsigned long *, irq_stack_ptr); > > -static inline bool on_stack(unsigned long sp, unsigned long size, > - unsigned long low, unsigned long high, > - enum stack_type type, struct stack_info *info) > -{ > - if (!low) > - return false; > - > - if (sp < low || sp + size < sp || sp + size > high) > - return false; > - > - if (info) { > - info->low = low; > - info->high = high; > - info->type = type; > - } > - return true; > -} > - > static inline bool on_irq_stack(unsigned long sp, unsigned long size, > struct stack_info *info) > { > diff --git a/arch/arm64/include/asm/stacktrace/common.h b/arch/arm64/include/asm/stacktrace/common.h > new file mode 100644 > index 000000000000..64ae4f6b06fe > --- /dev/null > +++ b/arch/arm64/include/asm/stacktrace/common.h > @@ -0,0 +1,105 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Common arm64 stack unwinder code. > + * > + * Copyright (C) 2012 ARM Ltd. > + */ > +#ifndef __ASM_STACKTRACE_COMMON_H > +#define __ASM_STACKTRACE_COMMON_H > + > +#include <linux/bitmap.h> > +#include <linux/bitops.h> > +#include <linux/types.h> > + > +enum stack_type { > + STACK_TYPE_UNKNOWN, > + STACK_TYPE_TASK, > + STACK_TYPE_IRQ, > + STACK_TYPE_OVERFLOW, > + STACK_TYPE_SDEI_NORMAL, > + STACK_TYPE_SDEI_CRITICAL, > + __NR_STACK_TYPES > +}; > + > +struct stack_info { > + unsigned long low; > + unsigned long high; > + enum stack_type type; > +}; > + > +/* > + * A snapshot of a frame record or fp/lr register values, along with some > + * accounting information necessary for robust unwinding. > + * > + * @fp: The fp value in the frame record (or the real fp) > + * @pc: The lr value in the frame record (or the real lr) > + * > + * @stacks_done: Stacks which have been entirely unwound, for which it is no > + * longer valid to unwind to. > + * > + * @prev_fp: The fp that pointed to this frame record, or a synthetic value > + * of 0. This is used to ensure that within a stack, each > + * subsequent frame record is at an increasing address. > + * @prev_type: The type of stack this frame record was on, or a synthetic > + * value of STACK_TYPE_UNKNOWN. This is used to detect a > + * transition from one stack to another. > + * > + * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance > + * associated with the most recently encountered replacement lr > + * value. > + * > + * @task: The task being unwound. > + */ > +struct unwind_state { > + unsigned long fp; > + unsigned long pc; > + DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); > + unsigned long prev_fp; > + enum stack_type prev_type; > +#ifdef CONFIG_KRETPROBES > + struct llist_node *kr_cur; > +#endif > + struct task_struct *task; > +}; > + > +static inline bool on_stack(unsigned long sp, unsigned long size, > + unsigned long low, unsigned long high, > + enum stack_type type, struct stack_info *info) > +{ > + if (!low) > + return false; > + > + if (sp < low || sp + size < sp || sp + size > high) > + return false; > + > + if (info) { > + info->low = low; > + info->high = high; > + info->type = type; > + } > + return true; > +} > + > +static inline void unwind_init_common(struct unwind_state *state, > + struct task_struct *task) > +{ > + state->task = task; > +#ifdef CONFIG_KRETPROBES > + state->kr_cur = NULL; > +#endif > + > + /* > + * Prime the first unwind. > + * > + * In unwind_next() we'll check that the FP points to a valid stack, > + * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be > + * treated as a transition to whichever stack that happens to be. The > + * prev_fp value won't be used, but we set it to 0 such that it is > + * definitely not an accessible stack address. > + */ > + bitmap_zero(state->stacks_done, __NR_STACK_TYPES); > + state->prev_fp = 0; > + state->prev_type = STACK_TYPE_UNKNOWN; > +} > + > +#endif /* __ASM_STACKTRACE_COMMON_H */ > diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c > index fcaa151b81f1..94a5dd2ab8fd 100644 > --- a/arch/arm64/kernel/stacktrace.c > +++ b/arch/arm64/kernel/stacktrace.c > @@ -18,63 +18,6 @@ > #include <asm/stack_pointer.h> > #include <asm/stacktrace.h> > > -/* > - * A snapshot of a frame record or fp/lr register values, along with some > - * accounting information necessary for robust unwinding. > - * > - * @fp: The fp value in the frame record (or the real fp) > - * @pc: The lr value in the frame record (or the real lr) > - * > - * @stacks_done: Stacks which have been entirely unwound, for which it is no > - * longer valid to unwind to. > - * > - * @prev_fp: The fp that pointed to this frame record, or a synthetic value > - * of 0. This is used to ensure that within a stack, each > - * subsequent frame record is at an increasing address. > - * @prev_type: The type of stack this frame record was on, or a synthetic > - * value of STACK_TYPE_UNKNOWN. This is used to detect a > - * transition from one stack to another. > - * > - * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance > - * associated with the most recently encountered replacement lr > - * value. > - * > - * @task: The task being unwound. > - */ > -struct unwind_state { > - unsigned long fp; > - unsigned long pc; > - DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); > - unsigned long prev_fp; > - enum stack_type prev_type; > -#ifdef CONFIG_KRETPROBES > - struct llist_node *kr_cur; > -#endif > - struct task_struct *task; > -}; > - > -static void unwind_init_common(struct unwind_state *state, > - struct task_struct *task) > -{ > - state->task = task; > -#ifdef CONFIG_KRETPROBES > - state->kr_cur = NULL; > -#endif > - > - /* > - * Prime the first unwind. > - * > - * In unwind_next() we'll check that the FP points to a valid stack, > - * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be > - * treated as a transition to whichever stack that happens to be. The > - * prev_fp value won't be used, but we set it to 0 such that it is > - * definitely not an accessible stack address. > - */ > - bitmap_zero(state->stacks_done, __NR_STACK_TYPES); > - state->prev_fp = 0; > - state->prev_type = STACK_TYPE_UNKNOWN; > -} > - > /* > * Start an unwind from a pt_regs. > * > -- > 2.37.0.170.g444d1eabd0-goog >
Hi, Can you please explain why you are targetting my @oracle.com email address with this patch set? This causes me problems as I use Outlook's Web interface for that which doesn't appear to cope with the threading, and most certainly is only capable of top-reply only which is against Linux kernel email standards. Thanks. On Thu, Jul 14, 2022 at 11:10:10PM -0700, Kalesh Singh wrote: > In order to reuse the arm64 stack unwinding logic for the nVHE > hypervisor stack, move the common code to a shared header > (arch/arm64/include/asm/stacktrace/common.h). > > The nVHE hypervisor cannot safely link against kernel code, so we > make use of the shared header to avoid duplicated logic later in > this series. > > Signed-off-by: Kalesh Singh <kaleshsingh@google.com> > --- > arch/arm64/include/asm/stacktrace.h | 35 +------ > arch/arm64/include/asm/stacktrace/common.h | 105 +++++++++++++++++++++ > arch/arm64/kernel/stacktrace.c | 57 ----------- > 3 files changed, 106 insertions(+), 91 deletions(-) > create mode 100644 arch/arm64/include/asm/stacktrace/common.h > > diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h > index aec9315bf156..79f455b37c84 100644 > --- a/arch/arm64/include/asm/stacktrace.h > +++ b/arch/arm64/include/asm/stacktrace.h > @@ -8,52 +8,19 @@ > #include <linux/percpu.h> > #include <linux/sched.h> > #include <linux/sched/task_stack.h> > -#include <linux/types.h> > #include <linux/llist.h> > > #include <asm/memory.h> > #include <asm/ptrace.h> > #include <asm/sdei.h> > > -enum stack_type { > - STACK_TYPE_UNKNOWN, > - STACK_TYPE_TASK, > - STACK_TYPE_IRQ, > - STACK_TYPE_OVERFLOW, > - STACK_TYPE_SDEI_NORMAL, > - STACK_TYPE_SDEI_CRITICAL, > - __NR_STACK_TYPES > -}; > - > -struct stack_info { > - unsigned long low; > - unsigned long high; > - enum stack_type type; > -}; > +#include <asm/stacktrace/common.h> > > extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, > const char *loglvl); > > DECLARE_PER_CPU(unsigned long *, irq_stack_ptr); > > -static inline bool on_stack(unsigned long sp, unsigned long size, > - unsigned long low, unsigned long high, > - enum stack_type type, struct stack_info *info) > -{ > - if (!low) > - return false; > - > - if (sp < low || sp + size < sp || sp + size > high) > - return false; > - > - if (info) { > - info->low = low; > - info->high = high; > - info->type = type; > - } > - return true; > -} > - > static inline bool on_irq_stack(unsigned long sp, unsigned long size, > struct stack_info *info) > { > diff --git a/arch/arm64/include/asm/stacktrace/common.h b/arch/arm64/include/asm/stacktrace/common.h > new file mode 100644 > index 000000000000..64ae4f6b06fe > --- /dev/null > +++ b/arch/arm64/include/asm/stacktrace/common.h > @@ -0,0 +1,105 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Common arm64 stack unwinder code. > + * > + * Copyright (C) 2012 ARM Ltd. > + */ > +#ifndef __ASM_STACKTRACE_COMMON_H > +#define __ASM_STACKTRACE_COMMON_H > + > +#include <linux/bitmap.h> > +#include <linux/bitops.h> > +#include <linux/types.h> > + > +enum stack_type { > + STACK_TYPE_UNKNOWN, > + STACK_TYPE_TASK, > + STACK_TYPE_IRQ, > + STACK_TYPE_OVERFLOW, > + STACK_TYPE_SDEI_NORMAL, > + STACK_TYPE_SDEI_CRITICAL, > + __NR_STACK_TYPES > +}; > + > +struct stack_info { > + unsigned long low; > + unsigned long high; > + enum stack_type type; > +}; > + > +/* > + * A snapshot of a frame record or fp/lr register values, along with some > + * accounting information necessary for robust unwinding. > + * > + * @fp: The fp value in the frame record (or the real fp) > + * @pc: The lr value in the frame record (or the real lr) > + * > + * @stacks_done: Stacks which have been entirely unwound, for which it is no > + * longer valid to unwind to. > + * > + * @prev_fp: The fp that pointed to this frame record, or a synthetic value > + * of 0. This is used to ensure that within a stack, each > + * subsequent frame record is at an increasing address. > + * @prev_type: The type of stack this frame record was on, or a synthetic > + * value of STACK_TYPE_UNKNOWN. This is used to detect a > + * transition from one stack to another. > + * > + * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance > + * associated with the most recently encountered replacement lr > + * value. > + * > + * @task: The task being unwound. > + */ > +struct unwind_state { > + unsigned long fp; > + unsigned long pc; > + DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); > + unsigned long prev_fp; > + enum stack_type prev_type; > +#ifdef CONFIG_KRETPROBES > + struct llist_node *kr_cur; > +#endif > + struct task_struct *task; > +}; > + > +static inline bool on_stack(unsigned long sp, unsigned long size, > + unsigned long low, unsigned long high, > + enum stack_type type, struct stack_info *info) > +{ > + if (!low) > + return false; > + > + if (sp < low || sp + size < sp || sp + size > high) > + return false; > + > + if (info) { > + info->low = low; > + info->high = high; > + info->type = type; > + } > + return true; > +} > + > +static inline void unwind_init_common(struct unwind_state *state, > + struct task_struct *task) > +{ > + state->task = task; > +#ifdef CONFIG_KRETPROBES > + state->kr_cur = NULL; > +#endif > + > + /* > + * Prime the first unwind. > + * > + * In unwind_next() we'll check that the FP points to a valid stack, > + * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be > + * treated as a transition to whichever stack that happens to be. The > + * prev_fp value won't be used, but we set it to 0 such that it is > + * definitely not an accessible stack address. > + */ > + bitmap_zero(state->stacks_done, __NR_STACK_TYPES); > + state->prev_fp = 0; > + state->prev_type = STACK_TYPE_UNKNOWN; > +} > + > +#endif /* __ASM_STACKTRACE_COMMON_H */ > diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c > index fcaa151b81f1..94a5dd2ab8fd 100644 > --- a/arch/arm64/kernel/stacktrace.c > +++ b/arch/arm64/kernel/stacktrace.c > @@ -18,63 +18,6 @@ > #include <asm/stack_pointer.h> > #include <asm/stacktrace.h> > > -/* > - * A snapshot of a frame record or fp/lr register values, along with some > - * accounting information necessary for robust unwinding. > - * > - * @fp: The fp value in the frame record (or the real fp) > - * @pc: The lr value in the frame record (or the real lr) > - * > - * @stacks_done: Stacks which have been entirely unwound, for which it is no > - * longer valid to unwind to. > - * > - * @prev_fp: The fp that pointed to this frame record, or a synthetic value > - * of 0. This is used to ensure that within a stack, each > - * subsequent frame record is at an increasing address. > - * @prev_type: The type of stack this frame record was on, or a synthetic > - * value of STACK_TYPE_UNKNOWN. This is used to detect a > - * transition from one stack to another. > - * > - * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance > - * associated with the most recently encountered replacement lr > - * value. > - * > - * @task: The task being unwound. > - */ > -struct unwind_state { > - unsigned long fp; > - unsigned long pc; > - DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); > - unsigned long prev_fp; > - enum stack_type prev_type; > -#ifdef CONFIG_KRETPROBES > - struct llist_node *kr_cur; > -#endif > - struct task_struct *task; > -}; > - > -static void unwind_init_common(struct unwind_state *state, > - struct task_struct *task) > -{ > - state->task = task; > -#ifdef CONFIG_KRETPROBES > - state->kr_cur = NULL; > -#endif > - > - /* > - * Prime the first unwind. > - * > - * In unwind_next() we'll check that the FP points to a valid stack, > - * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be > - * treated as a transition to whichever stack that happens to be. The > - * prev_fp value won't be used, but we set it to 0 such that it is > - * definitely not an accessible stack address. > - */ > - bitmap_zero(state->stacks_done, __NR_STACK_TYPES); > - state->prev_fp = 0; > - state->prev_type = STACK_TYPE_UNKNOWN; > -} > - > /* > * Start an unwind from a pt_regs. > * > -- > 2.37.0.170.g444d1eabd0-goog > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >
On Mon, Jul 18, 2022 at 5:52 AM Russell King (Oracle) <linux@armlinux.org.uk> wrote: > > Hi, > > Can you please explain why you are targetting my @oracle.com email > address with this patch set? > > This causes me problems as I use Outlook's Web interface for that > which doesn't appear to cope with the threading, and most certainly > is only capable of top-reply only which is against Linux kernel email > standards. Hi Russell, Sorry I wasn't aware of it (I got your oracle email from get_maintainer script). Going forward I'll use the one you responded from instead. Thanks, Kalesh > > Thanks. > > On Thu, Jul 14, 2022 at 11:10:10PM -0700, Kalesh Singh wrote: > > In order to reuse the arm64 stack unwinding logic for the nVHE > > hypervisor stack, move the common code to a shared header > > (arch/arm64/include/asm/stacktrace/common.h). > > > > The nVHE hypervisor cannot safely link against kernel code, so we > > make use of the shared header to avoid duplicated logic later in > > this series. > > > > Signed-off-by: Kalesh Singh <kaleshsingh@google.com> > > --- > > arch/arm64/include/asm/stacktrace.h | 35 +------ > > arch/arm64/include/asm/stacktrace/common.h | 105 +++++++++++++++++++++ > > arch/arm64/kernel/stacktrace.c | 57 ----------- > > 3 files changed, 106 insertions(+), 91 deletions(-) > > create mode 100644 arch/arm64/include/asm/stacktrace/common.h > > > > diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h > > index aec9315bf156..79f455b37c84 100644 > > --- a/arch/arm64/include/asm/stacktrace.h > > +++ b/arch/arm64/include/asm/stacktrace.h > > @@ -8,52 +8,19 @@ > > #include <linux/percpu.h> > > #include <linux/sched.h> > > #include <linux/sched/task_stack.h> > > -#include <linux/types.h> > > #include <linux/llist.h> > > > > #include <asm/memory.h> > > #include <asm/ptrace.h> > > #include <asm/sdei.h> > > > > -enum stack_type { > > - STACK_TYPE_UNKNOWN, > > - STACK_TYPE_TASK, > > - STACK_TYPE_IRQ, > > - STACK_TYPE_OVERFLOW, > > - STACK_TYPE_SDEI_NORMAL, > > - STACK_TYPE_SDEI_CRITICAL, > > - __NR_STACK_TYPES > > -}; > > - > > -struct stack_info { > > - unsigned long low; > > - unsigned long high; > > - enum stack_type type; > > -}; > > +#include <asm/stacktrace/common.h> > > > > extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, > > const char *loglvl); > > > > DECLARE_PER_CPU(unsigned long *, irq_stack_ptr); > > > > -static inline bool on_stack(unsigned long sp, unsigned long size, > > - unsigned long low, unsigned long high, > > - enum stack_type type, struct stack_info *info) > > -{ > > - if (!low) > > - return false; > > - > > - if (sp < low || sp + size < sp || sp + size > high) > > - return false; > > - > > - if (info) { > > - info->low = low; > > - info->high = high; > > - info->type = type; > > - } > > - return true; > > -} > > - > > static inline bool on_irq_stack(unsigned long sp, unsigned long size, > > struct stack_info *info) > > { > > diff --git a/arch/arm64/include/asm/stacktrace/common.h b/arch/arm64/include/asm/stacktrace/common.h > > new file mode 100644 > > index 000000000000..64ae4f6b06fe > > --- /dev/null > > +++ b/arch/arm64/include/asm/stacktrace/common.h > > @@ -0,0 +1,105 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Common arm64 stack unwinder code. > > + * > > + * Copyright (C) 2012 ARM Ltd. > > + */ > > +#ifndef __ASM_STACKTRACE_COMMON_H > > +#define __ASM_STACKTRACE_COMMON_H > > + > > +#include <linux/bitmap.h> > > +#include <linux/bitops.h> > > +#include <linux/types.h> > > + > > +enum stack_type { > > + STACK_TYPE_UNKNOWN, > > + STACK_TYPE_TASK, > > + STACK_TYPE_IRQ, > > + STACK_TYPE_OVERFLOW, > > + STACK_TYPE_SDEI_NORMAL, > > + STACK_TYPE_SDEI_CRITICAL, > > + __NR_STACK_TYPES > > +}; > > + > > +struct stack_info { > > + unsigned long low; > > + unsigned long high; > > + enum stack_type type; > > +}; > > + > > +/* > > + * A snapshot of a frame record or fp/lr register values, along with some > > + * accounting information necessary for robust unwinding. > > + * > > + * @fp: The fp value in the frame record (or the real fp) > > + * @pc: The lr value in the frame record (or the real lr) > > + * > > + * @stacks_done: Stacks which have been entirely unwound, for which it is no > > + * longer valid to unwind to. > > + * > > + * @prev_fp: The fp that pointed to this frame record, or a synthetic value > > + * of 0. This is used to ensure that within a stack, each > > + * subsequent frame record is at an increasing address. > > + * @prev_type: The type of stack this frame record was on, or a synthetic > > + * value of STACK_TYPE_UNKNOWN. This is used to detect a > > + * transition from one stack to another. > > + * > > + * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance > > + * associated with the most recently encountered replacement lr > > + * value. > > + * > > + * @task: The task being unwound. > > + */ > > +struct unwind_state { > > + unsigned long fp; > > + unsigned long pc; > > + DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); > > + unsigned long prev_fp; > > + enum stack_type prev_type; > > +#ifdef CONFIG_KRETPROBES > > + struct llist_node *kr_cur; > > +#endif > > + struct task_struct *task; > > +}; > > + > > +static inline bool on_stack(unsigned long sp, unsigned long size, > > + unsigned long low, unsigned long high, > > + enum stack_type type, struct stack_info *info) > > +{ > > + if (!low) > > + return false; > > + > > + if (sp < low || sp + size < sp || sp + size > high) > > + return false; > > + > > + if (info) { > > + info->low = low; > > + info->high = high; > > + info->type = type; > > + } > > + return true; > > +} > > + > > +static inline void unwind_init_common(struct unwind_state *state, > > + struct task_struct *task) > > +{ > > + state->task = task; > > +#ifdef CONFIG_KRETPROBES > > + state->kr_cur = NULL; > > +#endif > > + > > + /* > > + * Prime the first unwind. > > + * > > + * In unwind_next() we'll check that the FP points to a valid stack, > > + * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be > > + * treated as a transition to whichever stack that happens to be. The > > + * prev_fp value won't be used, but we set it to 0 such that it is > > + * definitely not an accessible stack address. > > + */ > > + bitmap_zero(state->stacks_done, __NR_STACK_TYPES); > > + state->prev_fp = 0; > > + state->prev_type = STACK_TYPE_UNKNOWN; > > +} > > + > > +#endif /* __ASM_STACKTRACE_COMMON_H */ > > diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c > > index fcaa151b81f1..94a5dd2ab8fd 100644 > > --- a/arch/arm64/kernel/stacktrace.c > > +++ b/arch/arm64/kernel/stacktrace.c > > @@ -18,63 +18,6 @@ > > #include <asm/stack_pointer.h> > > #include <asm/stacktrace.h> > > > > -/* > > - * A snapshot of a frame record or fp/lr register values, along with some > > - * accounting information necessary for robust unwinding. > > - * > > - * @fp: The fp value in the frame record (or the real fp) > > - * @pc: The lr value in the frame record (or the real lr) > > - * > > - * @stacks_done: Stacks which have been entirely unwound, for which it is no > > - * longer valid to unwind to. > > - * > > - * @prev_fp: The fp that pointed to this frame record, or a synthetic value > > - * of 0. This is used to ensure that within a stack, each > > - * subsequent frame record is at an increasing address. > > - * @prev_type: The type of stack this frame record was on, or a synthetic > > - * value of STACK_TYPE_UNKNOWN. This is used to detect a > > - * transition from one stack to another. > > - * > > - * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance > > - * associated with the most recently encountered replacement lr > > - * value. > > - * > > - * @task: The task being unwound. > > - */ > > -struct unwind_state { > > - unsigned long fp; > > - unsigned long pc; > > - DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); > > - unsigned long prev_fp; > > - enum stack_type prev_type; > > -#ifdef CONFIG_KRETPROBES > > - struct llist_node *kr_cur; > > -#endif > > - struct task_struct *task; > > -}; > > - > > -static void unwind_init_common(struct unwind_state *state, > > - struct task_struct *task) > > -{ > > - state->task = task; > > -#ifdef CONFIG_KRETPROBES > > - state->kr_cur = NULL; > > -#endif > > - > > - /* > > - * Prime the first unwind. > > - * > > - * In unwind_next() we'll check that the FP points to a valid stack, > > - * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be > > - * treated as a transition to whichever stack that happens to be. The > > - * prev_fp value won't be used, but we set it to 0 such that it is > > - * definitely not an accessible stack address. > > - */ > > - bitmap_zero(state->stacks_done, __NR_STACK_TYPES); > > - state->prev_fp = 0; > > - state->prev_type = STACK_TYPE_UNKNOWN; > > -} > > - > > /* > > * Start an unwind from a pt_regs. > > * > > -- > > 2.37.0.170.g444d1eabd0-goog > > > > > > _______________________________________________ > > linux-arm-kernel mailing list > > linux-arm-kernel@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > > > > -- > RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ > FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
On Mon, Jul 18, 2022 at 08:26:14AM -0700, Kalesh Singh wrote: > On Mon, Jul 18, 2022 at 5:52 AM Russell King (Oracle) > <linux@armlinux.org.uk> wrote: > > > > Hi, > > > > Can you please explain why you are targetting my @oracle.com email > > address with this patch set? > > > > This causes me problems as I use Outlook's Web interface for that > > which doesn't appear to cope with the threading, and most certainly > > is only capable of top-reply only which is against Linux kernel email > > standards. > > Hi Russell, > > Sorry I wasn't aware of it (I got your oracle email from > get_maintainer script). Going forward I'll use the one you responded > from instead. Oh, this is the very annoying behaviour of get_maintainer.pl default mode to think that if someone touches a file, they're interested in future changes to it. In this case, it's because we both touched arch/arm64/include/asm/memory.h back in November 2021, and this silly script thinks I'll still be interested. b89ddf4cca43 arm64/bpf: Remove 128MB limit for BPF JIT programs (The patch was originally developed for Oracle's UEK kernels, hence why it's got my @oracle.com address, but was later merged upstream. Interestingly, no one spotted that Alan Maguire's s-o-b should've been on it, as he was involved in the submission path to mainline.)
diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h index aec9315bf156..79f455b37c84 100644 --- a/arch/arm64/include/asm/stacktrace.h +++ b/arch/arm64/include/asm/stacktrace.h @@ -8,52 +8,19 @@ #include <linux/percpu.h> #include <linux/sched.h> #include <linux/sched/task_stack.h> -#include <linux/types.h> #include <linux/llist.h> #include <asm/memory.h> #include <asm/ptrace.h> #include <asm/sdei.h> -enum stack_type { - STACK_TYPE_UNKNOWN, - STACK_TYPE_TASK, - STACK_TYPE_IRQ, - STACK_TYPE_OVERFLOW, - STACK_TYPE_SDEI_NORMAL, - STACK_TYPE_SDEI_CRITICAL, - __NR_STACK_TYPES -}; - -struct stack_info { - unsigned long low; - unsigned long high; - enum stack_type type; -}; +#include <asm/stacktrace/common.h> extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, const char *loglvl); DECLARE_PER_CPU(unsigned long *, irq_stack_ptr); -static inline bool on_stack(unsigned long sp, unsigned long size, - unsigned long low, unsigned long high, - enum stack_type type, struct stack_info *info) -{ - if (!low) - return false; - - if (sp < low || sp + size < sp || sp + size > high) - return false; - - if (info) { - info->low = low; - info->high = high; - info->type = type; - } - return true; -} - static inline bool on_irq_stack(unsigned long sp, unsigned long size, struct stack_info *info) { diff --git a/arch/arm64/include/asm/stacktrace/common.h b/arch/arm64/include/asm/stacktrace/common.h new file mode 100644 index 000000000000..64ae4f6b06fe --- /dev/null +++ b/arch/arm64/include/asm/stacktrace/common.h @@ -0,0 +1,105 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Common arm64 stack unwinder code. + * + * Copyright (C) 2012 ARM Ltd. + */ +#ifndef __ASM_STACKTRACE_COMMON_H +#define __ASM_STACKTRACE_COMMON_H + +#include <linux/bitmap.h> +#include <linux/bitops.h> +#include <linux/types.h> + +enum stack_type { + STACK_TYPE_UNKNOWN, + STACK_TYPE_TASK, + STACK_TYPE_IRQ, + STACK_TYPE_OVERFLOW, + STACK_TYPE_SDEI_NORMAL, + STACK_TYPE_SDEI_CRITICAL, + __NR_STACK_TYPES +}; + +struct stack_info { + unsigned long low; + unsigned long high; + enum stack_type type; +}; + +/* + * A snapshot of a frame record or fp/lr register values, along with some + * accounting information necessary for robust unwinding. + * + * @fp: The fp value in the frame record (or the real fp) + * @pc: The lr value in the frame record (or the real lr) + * + * @stacks_done: Stacks which have been entirely unwound, for which it is no + * longer valid to unwind to. + * + * @prev_fp: The fp that pointed to this frame record, or a synthetic value + * of 0. This is used to ensure that within a stack, each + * subsequent frame record is at an increasing address. + * @prev_type: The type of stack this frame record was on, or a synthetic + * value of STACK_TYPE_UNKNOWN. This is used to detect a + * transition from one stack to another. + * + * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance + * associated with the most recently encountered replacement lr + * value. + * + * @task: The task being unwound. + */ +struct unwind_state { + unsigned long fp; + unsigned long pc; + DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); + unsigned long prev_fp; + enum stack_type prev_type; +#ifdef CONFIG_KRETPROBES + struct llist_node *kr_cur; +#endif + struct task_struct *task; +}; + +static inline bool on_stack(unsigned long sp, unsigned long size, + unsigned long low, unsigned long high, + enum stack_type type, struct stack_info *info) +{ + if (!low) + return false; + + if (sp < low || sp + size < sp || sp + size > high) + return false; + + if (info) { + info->low = low; + info->high = high; + info->type = type; + } + return true; +} + +static inline void unwind_init_common(struct unwind_state *state, + struct task_struct *task) +{ + state->task = task; +#ifdef CONFIG_KRETPROBES + state->kr_cur = NULL; +#endif + + /* + * Prime the first unwind. + * + * In unwind_next() we'll check that the FP points to a valid stack, + * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be + * treated as a transition to whichever stack that happens to be. The + * prev_fp value won't be used, but we set it to 0 such that it is + * definitely not an accessible stack address. + */ + bitmap_zero(state->stacks_done, __NR_STACK_TYPES); + state->prev_fp = 0; + state->prev_type = STACK_TYPE_UNKNOWN; +} + +#endif /* __ASM_STACKTRACE_COMMON_H */ diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index fcaa151b81f1..94a5dd2ab8fd 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -18,63 +18,6 @@ #include <asm/stack_pointer.h> #include <asm/stacktrace.h> -/* - * A snapshot of a frame record or fp/lr register values, along with some - * accounting information necessary for robust unwinding. - * - * @fp: The fp value in the frame record (or the real fp) - * @pc: The lr value in the frame record (or the real lr) - * - * @stacks_done: Stacks which have been entirely unwound, for which it is no - * longer valid to unwind to. - * - * @prev_fp: The fp that pointed to this frame record, or a synthetic value - * of 0. This is used to ensure that within a stack, each - * subsequent frame record is at an increasing address. - * @prev_type: The type of stack this frame record was on, or a synthetic - * value of STACK_TYPE_UNKNOWN. This is used to detect a - * transition from one stack to another. - * - * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance - * associated with the most recently encountered replacement lr - * value. - * - * @task: The task being unwound. - */ -struct unwind_state { - unsigned long fp; - unsigned long pc; - DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); - unsigned long prev_fp; - enum stack_type prev_type; -#ifdef CONFIG_KRETPROBES - struct llist_node *kr_cur; -#endif - struct task_struct *task; -}; - -static void unwind_init_common(struct unwind_state *state, - struct task_struct *task) -{ - state->task = task; -#ifdef CONFIG_KRETPROBES - state->kr_cur = NULL; -#endif - - /* - * Prime the first unwind. - * - * In unwind_next() we'll check that the FP points to a valid stack, - * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be - * treated as a transition to whichever stack that happens to be. The - * prev_fp value won't be used, but we set it to 0 such that it is - * definitely not an accessible stack address. - */ - bitmap_zero(state->stacks_done, __NR_STACK_TYPES); - state->prev_fp = 0; - state->prev_type = STACK_TYPE_UNKNOWN; -} - /* * Start an unwind from a pt_regs. *
In order to reuse the arm64 stack unwinding logic for the nVHE hypervisor stack, move the common code to a shared header (arch/arm64/include/asm/stacktrace/common.h). The nVHE hypervisor cannot safely link against kernel code, so we make use of the shared header to avoid duplicated logic later in this series. Signed-off-by: Kalesh Singh <kaleshsingh@google.com> --- arch/arm64/include/asm/stacktrace.h | 35 +------ arch/arm64/include/asm/stacktrace/common.h | 105 +++++++++++++++++++++ arch/arm64/kernel/stacktrace.c | 57 ----------- 3 files changed, 106 insertions(+), 91 deletions(-) create mode 100644 arch/arm64/include/asm/stacktrace/common.h