archives/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-03-08 05:44:45 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

scsi: buslogic: Reduce stack usage

Browse source 
Some randconfig builds run into excessive stack usage with gcc-14 or
higher, which use __attribute__((cold)) where earlier versions did not do
that:

drivers/scsi/BusLogic.c: In function 'blogic_init':
drivers/scsi/BusLogic.c:2398:1: error: the frame size of 1680 bytes is larger than 1536 bytes [-Werror=frame-larger-than=]

The problem is that a lot of code gets inlined into blogic_init() here. Two
functions stick out, but they are a bit different:

 - blogic_init_probeinfo_list() actually uses a few hundred bytes of kernel
   stack, which is a problem in combination with other functions that also
   do. Marking this one as noinline means that the stack slots get get
   reused between function calls

 - blogic_reportconfig() has a few large variables, but whenever it is not
   inlined into its caller, the compiler is actually smart enough to reuse
   stack slots for these automatically, so marking it as noinline saves
   most of the stack space by itself.

The combination of both of these should avoid the problem entirely.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260203163321.2598593-1-arnd@kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Arnd Bergmann 2026-02-03 17:33:15 +01:00 • committed by Martin K. Petersen
parent bbb8d98fb4
commit e17f0d4cc0
1 changed files with 4 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

6
drivers/scsi/BusLogic.c
View file

@ -920,7 +920,8 @@ static int __init blogic_init_fp_probeinfo(struct blogic_adapter *adapter)
a particular probe order.
*/
static void __init blogic_init_probeinfo_list(struct blogic_adapter *adapter)
static noinline_for_stack void __init
blogic_init_probeinfo_list(struct blogic_adapter *adapter)
{
/*
If a PCI BIOS is present, interrogate it for MultiMaster and
@ -1690,7 +1691,8 @@ common:
blogic_reportconfig reports the configuration of Host Adapter.
*/
static bool __init blogic_reportconfig(struct blogic_adapter *adapter)
static noinline_for_stack bool __init
blogic_reportconfig(struct blogic_adapter *adapter)
{
unsigned short alltgt_mask = (1 << adapter->maxdev) - 1;
unsigned short sync_ok, fast_ok;