Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
s390/vdso: Allow alternatives in vdso code
Implement the infrastructure required to allow alternatives in vdso code.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
authored by
Heiko Carstens
and committed by
Jason A. Donenfeld
e10863ff
a919390e
+23
+19
arch/s390/kernel/vdso.c
+19
arch/s390/kernel/vdso.c
···
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/mm.h>
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#include <linux/slab.h>
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#include <linux/smp.h>
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#include <linux/time_namespace.h>
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#include <linux/random.h>
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#include <vdso/datapage.h>
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#include <asm/alternative.h>
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#include <asm/vdso.h>
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extern char vdso64_start[], vdso64_end[];
···
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return pagelist;
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}
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static void vdso_apply_alternatives(void)
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{
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const struct elf64_shdr *alt, *shdr;
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struct alt_instr *start, *end;
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const struct elf64_hdr *hdr;
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hdr = (struct elf64_hdr *)vdso64_start;
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shdr = (void *)hdr + hdr->e_shoff;
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alt = find_section(hdr, shdr, ".altinstructions");
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if (!alt)
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return;
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start = (void *)hdr + alt->sh_offset;
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end = (void *)hdr + alt->sh_offset + alt->sh_size;
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apply_alternatives(start, end);
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}
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static int __init vdso_init(void)
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{
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vdso_apply_alternatives();
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vdso64_mapping.pages = vdso_setup_pages(vdso64_start, vdso64_end);
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if (IS_ENABLED(CONFIG_COMPAT))
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vdso32_mapping.pages = vdso_setup_pages(vdso32_start, vdso32_end);
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arch/s390/kernel/vdso64/vdso64.lds.S
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arch/s390/kernel/vdso64/vdso64.lds.S
···
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.rodata : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
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.rodata1 : { *(.rodata1) }
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. = ALIGN(8);
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.altinstructions : { *(.altinstructions) }
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.altinstr_replacement : { *(.altinstr_replacement) }
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.dynamic : { *(.dynamic) } :text :dynamic
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.eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr