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csky/vdso: Remove gettimeofday() and friends from VDSO

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The time-related VDSO functionality was introduced in 2021 in
commit 87f3248cdb ("csky: Reconstruct VDSO framework") and
commit 0d3b051adb ("csky: Add VDSO with GENERIC_GETTIMEOFDAY, GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO").

However the corresponding aux-vector entry AT_SYSINFO_EHDR was never
wired up, making these functions impossible to test or use.

The VDSO itself is kept as it also provides rt_sigreturn which is
exposed differently to userspace.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20241010-vdso-generic-base-v1-1-b64f0842d512@linutronix.de
This commit is contained in:
Thomas Weißschuh
2024-10-10 09:01:03 +02:00
committed by Thomas Gleixner
parent d4a65302dd
commit cf12469600
9 changed files with 2 additions and 218 deletions
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24
arch/csky/kernel/vdso.c
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@@ -8,23 +8,19 @@
#include <linux/slab.h>
#include <asm/page.h>
#include <vdso/datapage.h>
extern char vdso_start[], vdso_end[];
static unsigned int vdso_pages;
static struct page **vdso_pagelist;
static union vdso_data_store vdso_data_store __page_aligned_data;
struct vdso_data *vdso_data = vdso_data_store.data;
static int __init vdso_init(void)
{
unsigned int i;
vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT;
vdso_pagelist =
kcalloc(vdso_pages + 1, sizeof(struct page *), GFP_KERNEL);
kcalloc(vdso_pages, sizeof(struct page *), GFP_KERNEL);
if (unlikely(vdso_pagelist == NULL)) {
pr_err("vdso: pagelist allocation failed\n");
return -ENOMEM;
@@ -36,7 +32,6 @@ static int __init vdso_init(void)
pg = virt_to_page(vdso_start + (i << PAGE_SHIFT));
vdso_pagelist[i] = pg;
}
vdso_pagelist[i] = virt_to_page(vdso_data);
return 0;
}
@@ -52,11 +47,8 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
static struct vm_special_mapping vdso_mapping = {
.name = "[vdso]",
};
static struct vm_special_mapping vvar_mapping = {
.name = "[vvar]",
};
vdso_len = (vdso_pages + 1) << PAGE_SHIFT;
vdso_len = vdso_pages << PAGE_SHIFT;
mmap_write_lock(mm);
vdso_base = get_unmapped_area(NULL, 0, vdso_len, 0, 0);
@@ -85,15 +77,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
}
vdso_base += (vdso_pages << PAGE_SHIFT);
vvar_mapping.pages = &vdso_pagelist[vdso_pages];
vma = _install_special_mapping(mm, vdso_base, PAGE_SIZE,
(VM_READ | VM_MAYREAD), &vvar_mapping);
if (IS_ERR(vma)) {
ret = PTR_ERR(vma);
mm->context.vdso = NULL;
goto end;
}
ret = 0;
end:
mmap_write_unlock(mm);
@@ -104,8 +87,5 @@ const char *arch_vma_name(struct vm_area_struct *vma)
{
if (vma->vm_mm && (vma->vm_start == (long)vma->vm_mm->context.vdso))
return "[vdso]";
if (vma->vm_mm && (vma->vm_start ==
(long)vma->vm_mm->context.vdso + PAGE_SIZE))
return "[vdso_data]";
return NULL;
}