WARNING native_smp_call_function mask 2.6.22.6 SMP on Single CPU System

[Michael Stiller <ms@2scale.net>]

Hi,

i get the following warning if i call vfree some memory allocated by
vmalloc on a single cpu machine running 2.6.22.6 SMP:

WARNING: at arch/i386/kernel/smp.c:559 native_smp_call_function_mask()
 [<c010e77c>] native_smp_call_function_mask+0x145/0x14a
 [<c01cb32d>] idr_remove+0x102/0x163
 [<c010e43f>] do_flush_tlb_all+0x0/0x59
 [<c010e43f>] do_flush_tlb_all+0x0/0x59
 [<c010ea33>] smp_call_function+0x1c/0x29
 [<c0120922>] on_each_cpu+0x18/0x29
 [<c010e2e9>] flush_tlb_all+0x1b/0x1f
 [<c0155227>] remove_vm_area+0x4c/0x59
 [<c0155252>] __vunmap+0x1e/0xe5
 [<c011ccb7>] printk+0x1b/0x1f
 [<e0b15f21>] ring_release+0x1f7/0x28a [ring]
 [<c0247305>] sock_fasync+0x99/0x146
 [<c024826b>] sock_release+0x14/0x66
 [<c02486a8>] sock_close+0x1e/0x38
 [<c01600ee>] __fput+0x99/0x166
 [<c015db9f>] filp_close+0x3e/0x62
 [<c015ebf0>] sys_close+0x5f/0x9e
 [<c0103dba>] syscall_call+0x7/0xb
 =======================

I use the rvmalloc / rvfree functions copied from usbvideo.c:

static void rvfree(void *mem, unsigned long size)
{
        unsigned long adr;
        unsigned long pages = 0;

#if defined(RING_DEBUG)
        printk("RING: rvfree: %lu bytes\n", size);
#endif

        if (!mem)
                return;

        adr = (unsigned long) mem;
        while ((long) size > 0) {
                ClearPageReserved(vmalloc_to_page((void *)adr));
                pages++;
                adr += PAGE_SIZE;
                size -= PAGE_SIZE;
        }
#if defined(RING_DEBUG)
        printk("RING: rvfree: %lu pages\n", pages);
        printk("RING: rvfree: calling vfree....\n");
#endif
        vfree(mem);   // WARNING occurs here
        printk("RING: rvfree: after vfree....\n");
}


Any clues? 

Please cc me for answers. Thanks in advance. 

-Michael