| Message ID | 20190728231651.GA22123@embeddedor (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 2d0e988d8427b7b9c6d5c7835b6944405c038011 |
| Headers | show |
| Series | ARM/hw_breakpoint: Mark expected switch fall-throughs | expand |
On Sun, Jul 28, 2019 at 06:16:51PM -0500, Gustavo A. R. Silva wrote: > Mark switch cases where we are expecting to fall through. > > This patch fixes the following warnings: > > arch/arm/kernel/hw_breakpoint.c: In function 'hw_breakpoint_arch_parse': > arch/arm/kernel/hw_breakpoint.c:609:6: warning: this statement may fall through [-Wimplicit-fallthrough=] > if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2) > ^ > arch/arm/kernel/hw_breakpoint.c:611:2: note: here > case 3: > ^~~~ > arch/arm/kernel/hw_breakpoint.c:613:6: warning: this statement may fall through [-Wimplicit-fallthrough=] > if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1) > ^ > arch/arm/kernel/hw_breakpoint.c:615:2: note: here > default: > ^~~~~~~ > arch/arm/kernel/hw_breakpoint.c: In function 'arch_build_bp_info': > arch/arm/kernel/hw_breakpoint.c:544:6: warning: this statement may fall through [-Wimplicit-fallthrough=] > if ((hw->ctrl.type != ARM_BREAKPOINT_EXECUTE) > ^ > arch/arm/kernel/hw_breakpoint.c:547:2: note: here > default: > ^~~~~~~ > In file included from include/linux/kernel.h:11, > from include/linux/list.h:9, > from include/linux/preempt.h:11, > from include/linux/hardirq.h:5, > from arch/arm/kernel/hw_breakpoint.c:16: > arch/arm/kernel/hw_breakpoint.c: In function 'hw_breakpoint_pending': > include/linux/compiler.h:78:22: warning: this statement may fall through [-Wimplicit-fallthrough=] > # define unlikely(x) __builtin_expect(!!(x), 0) > ^~~~~~~~~~~~~~~~~~~~~~~~~~ > include/asm-generic/bug.h:136:2: note: in expansion of macro 'unlikely' > unlikely(__ret_warn_on); \ > ^~~~~~~~ > arch/arm/kernel/hw_breakpoint.c:863:3: note: in expansion of macro 'WARN' > WARN(1, "Asynchronous watchpoint exception taken. Debugging results may be unreliable\n"); > ^~~~ > arch/arm/kernel/hw_breakpoint.c:864:2: note: here > case ARM_ENTRY_SYNC_WATCHPOINT: > ^~~~ > arch/arm/kernel/hw_breakpoint.c: In function 'core_has_os_save_restore': > arch/arm/kernel/hw_breakpoint.c:910:6: warning: this statement may fall through [-Wimplicit-fallthrough=] > if (oslsr & ARM_OSLSR_OSLM0) > ^ > arch/arm/kernel/hw_breakpoint.c:912:2: note: here > default: > ^~~~~~~ > > Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Kees Cook <keescook@chromium.org> -Kees > --- > arch/arm/kernel/hw_breakpoint.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c > index af8b8e15f589..b0c195e3a06d 100644 > --- a/arch/arm/kernel/hw_breakpoint.c > +++ b/arch/arm/kernel/hw_breakpoint.c > @@ -544,6 +544,7 @@ static int arch_build_bp_info(struct perf_event *bp, > if ((hw->ctrl.type != ARM_BREAKPOINT_EXECUTE) > && max_watchpoint_len >= 8) > break; > + /* Else, fall through */ > default: > return -EINVAL; > } > @@ -608,10 +609,12 @@ int hw_breakpoint_arch_parse(struct perf_event *bp, > /* Allow halfword watchpoints and breakpoints. */ > if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2) > break; > + /* Else, fall through */ > case 3: > /* Allow single byte watchpoint. */ > if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1) > break; > + /* Else, fall through */ > default: > ret = -EINVAL; > goto out; > @@ -861,6 +864,7 @@ static int hw_breakpoint_pending(unsigned long addr, unsigned int fsr, > break; > case ARM_ENTRY_ASYNC_WATCHPOINT: > WARN(1, "Asynchronous watchpoint exception taken. Debugging results may be unreliable\n"); > + /* Fall through */ > case ARM_ENTRY_SYNC_WATCHPOINT: > watchpoint_handler(addr, fsr, regs); > break; > @@ -909,6 +913,7 @@ static bool core_has_os_save_restore(void) > ARM_DBG_READ(c1, c1, 4, oslsr); > if (oslsr & ARM_OSLSR_OSLM0) > return true; > + /* Else, fall through */ > default: > return false; > } > -- > 2.22.0 >
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index af8b8e15f589..b0c195e3a06d 100644 --- a/arch/arm/kernel/hw_breakpoint.c +++ b/arch/arm/kernel/hw_breakpoint.c @@ -544,6 +544,7 @@ static int arch_build_bp_info(struct perf_event *bp, if ((hw->ctrl.type != ARM_BREAKPOINT_EXECUTE) && max_watchpoint_len >= 8) break; + /* Else, fall through */ default: return -EINVAL; } @@ -608,10 +609,12 @@ int hw_breakpoint_arch_parse(struct perf_event *bp, /* Allow halfword watchpoints and breakpoints. */ if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2) break; + /* Else, fall through */ case 3: /* Allow single byte watchpoint. */ if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1) break; + /* Else, fall through */ default: ret = -EINVAL; goto out; @@ -861,6 +864,7 @@ static int hw_breakpoint_pending(unsigned long addr, unsigned int fsr, break; case ARM_ENTRY_ASYNC_WATCHPOINT: WARN(1, "Asynchronous watchpoint exception taken. Debugging results may be unreliable\n"); + /* Fall through */ case ARM_ENTRY_SYNC_WATCHPOINT: watchpoint_handler(addr, fsr, regs); break; @@ -909,6 +913,7 @@ static bool core_has_os_save_restore(void) ARM_DBG_READ(c1, c1, 4, oslsr); if (oslsr & ARM_OSLSR_OSLM0) return true; + /* Else, fall through */ default: return false; }
Mark switch cases where we are expecting to fall through. This patch fixes the following warnings: arch/arm/kernel/hw_breakpoint.c: In function 'hw_breakpoint_arch_parse': arch/arm/kernel/hw_breakpoint.c:609:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2) ^ arch/arm/kernel/hw_breakpoint.c:611:2: note: here case 3: ^~~~ arch/arm/kernel/hw_breakpoint.c:613:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1) ^ arch/arm/kernel/hw_breakpoint.c:615:2: note: here default: ^~~~~~~ arch/arm/kernel/hw_breakpoint.c: In function 'arch_build_bp_info': arch/arm/kernel/hw_breakpoint.c:544:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if ((hw->ctrl.type != ARM_BREAKPOINT_EXECUTE) ^ arch/arm/kernel/hw_breakpoint.c:547:2: note: here default: ^~~~~~~ In file included from include/linux/kernel.h:11, from include/linux/list.h:9, from include/linux/preempt.h:11, from include/linux/hardirq.h:5, from arch/arm/kernel/hw_breakpoint.c:16: arch/arm/kernel/hw_breakpoint.c: In function 'hw_breakpoint_pending': include/linux/compiler.h:78:22: warning: this statement may fall through [-Wimplicit-fallthrough=] # define unlikely(x) __builtin_expect(!!(x), 0) ^~~~~~~~~~~~~~~~~~~~~~~~~~ include/asm-generic/bug.h:136:2: note: in expansion of macro 'unlikely' unlikely(__ret_warn_on); \ ^~~~~~~~ arch/arm/kernel/hw_breakpoint.c:863:3: note: in expansion of macro 'WARN' WARN(1, "Asynchronous watchpoint exception taken. Debugging results may be unreliable\n"); ^~~~ arch/arm/kernel/hw_breakpoint.c:864:2: note: here case ARM_ENTRY_SYNC_WATCHPOINT: ^~~~ arch/arm/kernel/hw_breakpoint.c: In function 'core_has_os_save_restore': arch/arm/kernel/hw_breakpoint.c:910:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (oslsr & ARM_OSLSR_OSLM0) ^ arch/arm/kernel/hw_breakpoint.c:912:2: note: here default: ^~~~~~~ Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- arch/arm/kernel/hw_breakpoint.c | 5 +++++ 1 file changed, 5 insertions(+)