[PATCH 1/2] LoongArch: Add pad structure members for explicit alignment

From: Qing Zhang
Date: Tue Apr 18 2023 - 05:14:04 EST


This is done in order to easily calculate the number of breakpoints
in hw_break_get.

Signed-off-by: Qing Zhang <zhangqing@xxxxxxxxxxx>
---
arch/loongarch/include/uapi/asm/ptrace.h | 3 ++-
arch/loongarch/kernel/ptrace.c | 13 +++++++++----
2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/arch/loongarch/include/uapi/asm/ptrace.h b/arch/loongarch/include/uapi/asm/ptrace.h
index 2282ae1fd3b6..06e3be52cb04 100644
--- a/arch/loongarch/include/uapi/asm/ptrace.h
+++ b/arch/loongarch/include/uapi/asm/ptrace.h
@@ -57,11 +57,12 @@ struct user_lasx_state {
};

struct user_watch_state {
- uint16_t dbg_info;
+ uint64_t dbg_info;
struct {
uint64_t addr;
uint64_t mask;
uint32_t ctrl;
+ uint32_t pad;
} dbg_regs[8];
};

diff --git a/arch/loongarch/kernel/ptrace.c b/arch/loongarch/kernel/ptrace.c
index 0c7c41e41cad..9c3bc1bbf2ff 100644
--- a/arch/loongarch/kernel/ptrace.c
+++ b/arch/loongarch/kernel/ptrace.c
@@ -475,10 +475,10 @@ static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type,
return 0;
}

-static int ptrace_hbp_get_resource_info(unsigned int note_type, u16 *info)
+static int ptrace_hbp_get_resource_info(unsigned int note_type, u64 *info)
{
u8 num;
- u16 reg = 0;
+ u64 reg = 0;

switch (note_type) {
case NT_LOONGARCH_HW_BREAK:
@@ -616,7 +616,7 @@ static int hw_break_get(struct task_struct *target,
const struct user_regset *regset,
struct membuf to)
{
- u16 info;
+ u64 info;
u32 ctrl;
u64 addr, mask;
int ret, idx = 0;
@@ -646,6 +646,7 @@ static int hw_break_get(struct task_struct *target,
membuf_store(&to, addr);
membuf_store(&to, mask);
membuf_store(&to, ctrl);
+ membuf_zero(&to, sizeof(u32));
idx++;
}

@@ -662,7 +663,7 @@ static int hw_break_set(struct task_struct *target,
int ret, idx = 0, offset, limit;
unsigned int note_type = regset->core_note_type;

- /* Resource info */
+ /* Resource info and pad */
offset = offsetof(struct user_watch_state, dbg_regs);
user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);

@@ -704,6 +705,10 @@ static int hw_break_set(struct task_struct *target,
if (ret)
return ret;
offset += PTRACE_HBP_CTRL_SZ;
+
+ user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+ offset, offset + PTRACE_HBP_PAD_SZ);
+ offset += PTRACE_HBP_PAD_SZ;
idx++;
}

--
2.20.1