On 08.06.22 18:59, Bezdeka, Florian (T CED SES-DE) wrote: > On Wed, 2022-06-08 at 17:02 +0200, Jan Kiszka wrote: >> On 25.05.22 11:56, Florian Bezdeka wrote: >>> Parts of the FPU tests were skipped when one of the following config >>> options was enabled, shadowing a real test issue that was triggered by >>> high load on the system. The options: >>> - CONFIG_X86_USE_3DNOW >>> - CONFIG_MD_RAID456 >>> - CONFIG_MD_RAID456_MODULE >>> >>> As the FPU initialization is fixed now, we can enable the tests >>> unconditionally. >>> >>> Signed-off-by: Florian Bezdeka <[email protected]> >>> --- >>> .../arch/x86/ipipe/include/asm/xenomai/fptest.h | 13 ------------- >>> 1 file changed, 13 deletions(-) >>> >>> diff --git a/kernel/cobalt/arch/x86/ipipe/include/asm/xenomai/fptest.h >>> b/kernel/cobalt/arch/x86/ipipe/include/asm/xenomai/fptest.h >>> index ccf7afa11..7a2b17d75 100644 >>> --- a/kernel/cobalt/arch/x86/ipipe/include/asm/xenomai/fptest.h >>> +++ b/kernel/cobalt/arch/x86/ipipe/include/asm/xenomai/fptest.h >>> @@ -36,19 +36,6 @@ static inline void fp_init(void) >>> >>> static inline int fp_linux_begin(void) >>> { >>> -#if defined(CONFIG_X86_USE_3DNOW) \ >>> - || defined(CONFIG_MD_RAID456) || defined(CONFIG_MD_RAID456_MODULE) >>> - /* Ther kernel uses x86 FPU, we can not also use it in our tests. */ >>> - static int once = 0; >>> - if (!once) { >>> - once = 1; >>> - printk("%s:%d: Warning: Linux is compiled to use FPU in " >>> - "kernel-space.\nFor this reason, switchtest can not " >>> - "test using FPU in Linux kernel-space.\n", >>> - __FILE__, __LINE__); >>> - } >>> - return -EBUSY; >>> -#endif /* 3DNow or RAID 456 */ >>> kernel_fpu_begin(); >>> /* kernel_fpu_begin() does no re-initialize the fpu context, but >>> fp_regs_set() implicitely expects an initialized fpu context, so >> >> Hmm, I'm not yet fully convinced from reading both commit logs that the >> one fix actually obsoletes this check. Did it really only paper over a >> simple bug? > > I don't have the full history here, but it seems that this was kind of > double protection. > > So far all tests did not bring up any further issues. > > On systems with RAID (=systems with one of the mentioned options > enabled) FPU usage is much more likely and bugs would trigger more > likely. I would like to enable the FPU systems especially on such > systems. > > But: In case we have more undiscovered bugs in this area, it might > happen that we damage a RAID based file system. It seems Gilles had > such a system and tried to prevent FS damage this way. >
OK, it's just a test setup in the end - let's dare it. Applied both to stable/v3.2. Jan -- Siemens AG, Technology Competence Center Embedded Linux
