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s390: remove 31 bit support

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Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.

The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e58 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.

Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens
2015-02-12 13:08:27 +01:00
committed by Martin Schwidefsky
parent 1833c9f647
commit 5a79859ae0
97 changed files with 170 additions and 6016 deletions
Download Patch File Download Diff File Expand all files Collapse all files

72
arch/s390/kernel/setup.c
View File

@@ -92,10 +92,8 @@ EXPORT_SYMBOL(VMALLOC_END);
struct page *vmemmap;
EXPORT_SYMBOL(vmemmap);
#ifdef CONFIG_64BIT
unsigned long MODULES_VADDR;
unsigned long MODULES_END;
#endif
/* An array with a pointer to the lowcore of every CPU. */
struct _lowcore *lowcore_ptr[NR_CPUS];
@@ -334,19 +332,10 @@ static void __init setup_lowcore(void)
lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
MAX_FACILITY_BIT/8);
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE) {
lc->extended_save_area_addr = (__u32)
__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
/* enable extended save area */
__ctl_set_bit(14, 29);
}
#else
if (MACHINE_HAS_VX)
lc->vector_save_area_addr =
(unsigned long) &lc->vector_save_area;
lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
#endif
lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
lc->async_enter_timer = S390_lowcore.async_enter_timer;
lc->exit_timer = S390_lowcore.exit_timer;
@@ -450,7 +439,6 @@ static void __init setup_memory_end(void)
unsigned long vmax, vmalloc_size, tmp;
/* Choose kernel address space layout: 2, 3, or 4 levels. */
#ifdef CONFIG_64BIT
vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
@@ -462,12 +450,6 @@ static void __init setup_memory_end(void)
MODULES_END = vmax;
MODULES_VADDR = MODULES_END - MODULES_LEN;
VMALLOC_END = MODULES_VADDR;
#else
vmalloc_size = VMALLOC_END ?: 96UL << 20;
vmax = 1UL << 31; /* 2-level kernel page table */
/* vmalloc area is at the end of the kernel address space. */
VMALLOC_END = vmax;
#endif
VMALLOC_START = vmax - vmalloc_size;
/* Split remaining virtual space between 1:1 mapping & vmemmap array */
@@ -754,7 +736,6 @@ static void __init setup_hwcaps(void)
if (MACHINE_HAS_HPAGE)
elf_hwcap |= HWCAP_S390_HPAGE;
#if defined(CONFIG_64BIT)
/*
* 64-bit register support for 31-bit processes
* HWCAP_S390_HIGH_GPRS is bit 9.
@@ -772,22 +753,15 @@ static void __init setup_hwcaps(void)
*/
if (test_facility(129))
elf_hwcap |= HWCAP_S390_VXRS;
#endif
get_cpu_id(&cpu_id);
add_device_randomness(&cpu_id, sizeof(cpu_id));
switch (cpu_id.machine) {
case 0x9672:
#if !defined(CONFIG_64BIT)
default: /* Use "g5" as default for 31 bit kernels. */
#endif
strcpy(elf_platform, "g5");
break;
case 0x2064:
case 0x2066:
#if defined(CONFIG_64BIT)
default: /* Use "z900" as default for 64 bit kernels. */
#endif
strcpy(elf_platform, "z900");
break;
case 0x2084:
@@ -839,19 +813,6 @@ void __init setup_arch(char **cmdline_p)
/*
* print what head.S has found out about the machine
*/
#ifndef CONFIG_64BIT
if (MACHINE_IS_VM)
pr_info("Linux is running as a z/VM "
"guest operating system in 31-bit mode\n");
else if (MACHINE_IS_LPAR)
pr_info("Linux is running natively in 31-bit mode\n");
if (MACHINE_HAS_IEEE)
pr_info("The hardware system has IEEE compatible "
"floating point units\n");
else
pr_info("The hardware system has no IEEE compatible "
"floating point units\n");
#else /* CONFIG_64BIT */
if (MACHINE_IS_VM)
pr_info("Linux is running as a z/VM "
"guest operating system in 64-bit mode\n");
@@ -859,7 +820,6 @@ void __init setup_arch(char **cmdline_p)
pr_info("Linux is running under KVM in 64-bit mode\n");
else if (MACHINE_IS_LPAR)
pr_info("Linux is running natively in 64-bit mode\n");
#endif /* CONFIG_64BIT */
/* Have one command line that is parsed and saved in /proc/cmdline */
/* boot_command_line has been already set up in early.c */
@@ -930,35 +890,3 @@ void __init setup_arch(char **cmdline_p)
/* Add system specific data to the random pool */
setup_randomness();
}
#ifdef CONFIG_32BIT
static int no_removal_warning __initdata;
static int __init parse_no_removal_warning(char *str)
{
no_removal_warning = 1;
return 0;
}
__setup("no_removal_warning", parse_no_removal_warning);
static int __init removal_warning(void)
{
if (no_removal_warning)
return 0;
printk(KERN_ALERT "\n\n");
printk(KERN_CONT "Warning - you are using a 31 bit kernel!\n\n");
printk(KERN_CONT "We plan to remove 31 bit kernel support from the kernel sources in March 2015.\n");
printk(KERN_CONT "Currently we assume that nobody is using the 31 bit kernel on old 31 bit\n");
printk(KERN_CONT "hardware anymore. If you think that the code should not be removed and also\n");
printk(KERN_CONT "future versions of the Linux kernel should be able to run in 31 bit mode\n");
printk(KERN_CONT "please let us know. Please write to:\n");
printk(KERN_CONT "linux390@de.ibm.com (mail address) and/or\n");
printk(KERN_CONT "linux-s390@vger.kernel.org (mailing list).\n\n");
printk(KERN_CONT "Thank you!\n\n");
printk(KERN_CONT "If this kernel runs on a 64 bit machine you may consider using a 64 bit kernel.\n");
printk(KERN_CONT "This message can be disabled with the \"no_removal_warning\" kernel parameter.\n");
schedule_timeout_uninterruptible(300 * HZ);
return 0;
}
early_initcall(removal_warning);
#endif