diff mbox series

ARM: vexpress: spc: fix uniprocessor initialization

Message ID 20210323125649.1930186-1-arnd@kernel.org (mailing list archive)
State New, archived
Headers show
Series ARM: vexpress: spc: fix uniprocessor initialization | expand

Commit Message

Arnd Bergmann March 23, 2021, 12:56 p.m. UTC 
From: Arnd Bergmann <arnd@arndb.de>

When CONFIG_SMP is disabled, topology_physical_package_id()
returns -1 and gcc notices undefined behavior:

arch/arm/mach-versatile/spc.c: In function 've_spc_clk_init':
arch/arm/mach-versatile/spc.c:583:21: error: array subscript -1 is below array bounds of 'bool[2]' {aka '_Bool[2]'} [-Werror=array-bounds]
  583 |   if (init_opp_table[cluster])
      |       ~~~~~~~~~~~~~~^~~~~~~~~
arch/arm/mach-versatile/spc.c:556:7: note: while referencing 'init_opp_table'
  556 |  bool init_opp_table[MAX_CLUSTERS] = { false };
      |       ^~~~~~~~~~~~~~

It's not clear to me what the correct behavior should be, but
it seems safe to just not continue with the initialization.

Fixes: 2a76352ad2cc ("ARM: vexpress: Set-up shared OPP table instead of individual for each CPU")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/arm/mach-versatile/spc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Sudeep Holla March 26, 2021, 1:41 p.m. UTC | #1 
Hi Arnd,

Sorry for the delay

On Tue, Mar 23, 2021 at 01:56:38PM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> When CONFIG_SMP is disabled, topology_physical_package_id()
> returns -1 and gcc notices undefined behavior:
> 
> arch/arm/mach-versatile/spc.c: In function 've_spc_clk_init':
> arch/arm/mach-versatile/spc.c:583:21: error: array subscript -1 is below array bounds of 'bool[2]' {aka '_Bool[2]'} [-Werror=array-bounds]
>   583 |   if (init_opp_table[cluster])
>       |       ~~~~~~~~~~~~~~^~~~~~~~~
> arch/arm/mach-versatile/spc.c:556:7: note: while referencing 'init_opp_table'
>   556 |  bool init_opp_table[MAX_CLUSTERS] = { false };
>       |       ^~~~~~~~~~~~~~
> 
> It's not clear to me what the correct behavior should be, but
> it seems safe to just not continue with the initialization.
> 

I don't have any other patches for vexpress platform or driver support.
Can you apply this directly ? Assuming that,

Acked-by: Sudeep Holla <sudeep.holla@arm.com>

--
Regards,
Sudeep
diff mbox series

Patch

diff --git a/arch/arm/mach-versatile/spc.c b/arch/arm/mach-versatile/spc.c
index 1da11bdb1dfb..1c6500c4e6a1 100644
--- a/arch/arm/mach-versatile/spc.c
+++ b/arch/arm/mach-versatile/spc.c
@@ -580,7 +580,7 @@  static int __init ve_spc_clk_init(void)
 		}
 
 		cluster = topology_physical_package_id(cpu_dev->id);
-		if (init_opp_table[cluster])
+		if (cluster < 0 || init_opp_table[cluster])
 			continue;
 
 		if (ve_init_opp_table(cpu_dev))