From a5c2a893dbd4956a72fb261e8790d19f67b52c99 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 28 Nov 2012 11:50:28 -0800 Subject: [PATCH] x86, 386 removal: Remove CONFIG_X86_WP_WORKS_OK All 486+ CPUs support WP in supervisor mode, so remove the fallback 386 support code. Signed-off-by: H. Peter Anvin Link: http://lkml.kernel.org/r/1354132230-21854-7-git-send-email-hpa@linux.intel.com --- arch/x86/Kconfig.cpu | 3 -- arch/x86/include/asm/uaccess.h | 42 ------------------------- arch/x86/lib/usercopy_32.c | 57 ---------------------------------- arch/x86/mm/init_32.c | 5 +-- 4 files changed, 1 insertion(+), 106 deletions(-) diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu index d3bdc18af1f0..159ee9c824c9 100644 --- a/arch/x86/Kconfig.cpu +++ b/arch/x86/Kconfig.cpu @@ -325,9 +325,6 @@ config X86_INVD_BUG def_bool y depends on M486 -config X86_WP_WORKS_OK - def_bool y - config X86_POPAD_OK def_bool y depends on X86_32 diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 7ccf8d131535..1709801d18ec 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -237,8 +237,6 @@ extern void __put_user_2(void); extern void __put_user_4(void); extern void __put_user_8(void); -#ifdef CONFIG_X86_WP_WORKS_OK - /** * put_user: - Write a simple value into user space. * @x: Value to copy to user space. @@ -326,29 +324,6 @@ do { \ } \ } while (0) -#else - -#define __put_user_size(x, ptr, size, retval, errret) \ -do { \ - __typeof__(*(ptr))__pus_tmp = x; \ - retval = 0; \ - \ - if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0)) \ - retval = errret; \ -} while (0) - -#define put_user(x, ptr) \ -({ \ - int __ret_pu; \ - __typeof__(*(ptr))__pus_tmp = x; \ - __ret_pu = 0; \ - if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, \ - sizeof(*(ptr))) != 0)) \ - __ret_pu = -EFAULT; \ - __ret_pu; \ -}) -#endif - #ifdef CONFIG_X86_32 #define __get_user_asm_u64(x, ptr, retval, errret) (x) = __get_user_bad() #define __get_user_asm_ex_u64(x, ptr) (x) = __get_user_bad() @@ -543,29 +518,12 @@ struct __large_struct { unsigned long buf[100]; }; (x) = (__force __typeof__(*(ptr)))__gue_val; \ } while (0) -#ifdef CONFIG_X86_WP_WORKS_OK - #define put_user_try uaccess_try #define put_user_catch(err) uaccess_catch(err) #define put_user_ex(x, ptr) \ __put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) -#else /* !CONFIG_X86_WP_WORKS_OK */ - -#define put_user_try do { \ - int __uaccess_err = 0; - -#define put_user_catch(err) \ - (err) |= __uaccess_err; \ -} while (0) - -#define put_user_ex(x, ptr) do { \ - __uaccess_err |= __put_user(x, ptr); \ -} while (0) - -#endif /* CONFIG_X86_WP_WORKS_OK */ - extern unsigned long copy_from_user_nmi(void *to, const void __user *from, unsigned long n); extern __must_check long diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c index 98f6d6b68f5a..f0312d746402 100644 --- a/arch/x86/lib/usercopy_32.c +++ b/arch/x86/lib/usercopy_32.c @@ -570,63 +570,6 @@ do { \ unsigned long __copy_to_user_ll(void __user *to, const void *from, unsigned long n) { -#ifndef CONFIG_X86_WP_WORKS_OK - if (unlikely(boot_cpu_data.wp_works_ok == 0) && - ((unsigned long)to) < TASK_SIZE) { - /* - * When we are in an atomic section (see - * mm/filemap.c:file_read_actor), return the full - * length to take the slow path. - */ - if (in_atomic()) - return n; - - /* - * CPU does not honor the WP bit when writing - * from supervisory mode, and due to preemption or SMP, - * the page tables can change at any time. - * Do it manually. Manfred - */ - while (n) { - unsigned long offset = ((unsigned long)to)%PAGE_SIZE; - unsigned long len = PAGE_SIZE - offset; - int retval; - struct page *pg; - void *maddr; - - if (len > n) - len = n; - -survive: - down_read(¤t->mm->mmap_sem); - retval = get_user_pages(current, current->mm, - (unsigned long)to, 1, 1, 0, &pg, NULL); - - if (retval == -ENOMEM && is_global_init(current)) { - up_read(¤t->mm->mmap_sem); - congestion_wait(BLK_RW_ASYNC, HZ/50); - goto survive; - } - - if (retval != 1) { - up_read(¤t->mm->mmap_sem); - break; - } - - maddr = kmap_atomic(pg); - memcpy(maddr + offset, from, len); - kunmap_atomic(maddr); - set_page_dirty_lock(pg); - put_page(pg); - up_read(¤t->mm->mmap_sem); - - from += len; - to += len; - n -= len; - } - return n; - } -#endif stac(); if (movsl_is_ok(to, from, n)) __copy_user(to, from, n); diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 11a58001b4ce..745d66b843c8 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -715,10 +715,7 @@ static void __init test_wp_bit(void) if (!boot_cpu_data.wp_works_ok) { printk(KERN_CONT "No.\n"); -#ifdef CONFIG_X86_WP_WORKS_OK - panic( - "This kernel doesn't support CPU's with broken WP. Recompile it for a 386!"); -#endif + panic("Linux doesn't support CPUs with broken WP."); } else { printk(KERN_CONT "Ok.\n"); }