Commit 31c3a1e8 authored by Michal Suchanek's avatar Michal Suchanek Committed by Greg Kroah-Hartman

powerpc/64s: Patch barrier_nospec in modules

commit 815069ca upstream.

Note that unlike RFI which is patched only in kernel the nospec state
reflects settings at the time the module was loaded.

Iterating all modules and re-patching every time the settings change
is not implemented.

Based on lwsync patching.
Signed-off-by: default avatarMichal Suchanek <>
Signed-off-by: default avatarMichael Ellerman <>
Signed-off-by: default avatarGreg Kroah-Hartman <>
parent f1a6390a
......@@ -53,6 +53,13 @@ enum l1d_flush_type {
void setup_rfi_flush(enum l1d_flush_type, bool enable);
void do_rfi_flush_fixups(enum l1d_flush_type types);
void do_barrier_nospec_fixups(bool enable);
extern bool barrier_nospec_enabled;
void do_barrier_nospec_fixups_range(bool enable, void *start, void *end);
static inline void do_barrier_nospec_fixups_range(bool enable, void *start, void *end) { };
#endif /* !__ASSEMBLY__ */
......@@ -72,6 +72,12 @@ int module_finalize(const Elf_Ehdr *hdr,
(void *)sect->sh_addr,
(void *)sect->sh_addr + sect->sh_size);
sect = find_section(hdr, sechdrs, "__spec_barrier_fixup");
if (sect != NULL)
(void *)sect->sh_addr,
(void *)sect->sh_addr + sect->sh_size);
sect = find_section(hdr, sechdrs, "__lwsync_fixup");
......@@ -15,7 +15,7 @@
unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT;
static bool barrier_nospec_enabled;
bool barrier_nospec_enabled;
static void enable_barrier_nospec(bool enable)
......@@ -278,14 +278,14 @@ void do_rfi_flush_fixups(enum l1d_flush_type types)
: "unknown");
void do_barrier_nospec_fixups(bool enable)
void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
unsigned int instr, *dest;
long *start, *end;
int i;
start = PTRRELOC(&__start___barrier_nospec_fixup),
end = PTRRELOC(&__stop___barrier_nospec_fixup);
start = fixup_start;
end = fixup_end;
instr = 0x60000000; /* nop */
......@@ -304,6 +304,16 @@ void do_barrier_nospec_fixups(bool enable)
printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
void do_barrier_nospec_fixups(bool enable)
void *start, *end;
start = PTRRELOC(&__start___barrier_nospec_fixup),
end = PTRRELOC(&__stop___barrier_nospec_fixup);
do_barrier_nospec_fixups_range(enable, start, end);
#endif /* CONFIG_PPC_BOOK3S_64 */
void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
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