Fix note_syscall_leave_s to avoid unaligned access #2005
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YuuichiNakamura
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Summary
Currently
struct note_syscall_leave_scontains a member of uintptr_t (nsc_result).Because note struct is stored with packed in the buffer, nsc_result may placed on unaligned address.
If the processor architecture doesn't support unaligned word access (ex. Cortex-M0), accessing nsc_result may crash.
This PR fixes the member nsc_result to uint8_t array like nc_pid and nc_systime.
Additionally this PR fixes similar problem in
struct note_spinlock_s.Impact
struct note_syscall_leave_sandstruct note_spinlock_sare changed. All app codes using them must be fixed.(Another PR for apps (apache/nuttx-apps#429) fixes them)
Testing
Tested with spresense:nsh
Because Cortex-M4 supports unaligned access by default, I have intentionally modified CPU control register to disable unaligned access for test.
This crashes "trace dump" command. The PR fixes it.