arm64/boot: Move global CPU override variables out of BSS

Accessing BSS will no longer be permitted from the startup code in
arch/arm64/kernel/pi, as some of it executes before BSS is cleared.
Clearing BSS earlier would involve managing cache coherency explicitly
in software, which is a hassle we prefer to avoid.

So move some variables that are assigned by the startup code out of BSS
and into .data.

Signed-off-by: Ard Biesheuvel <[email protected]>
Tested-by: Yeoreum Yun <[email protected]>
Reviewed-by: Yeoreum Yun <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>

Author: ardbiesheuvel

arch/arm64/kernel/cpufeature.c

@@ -758,17 +758,17 @@ static const struct arm64_ftr_bits ftr_raz[] = {
 #define ARM64_FTR_REG(id, table)		\
 	__ARM64_FTR_REG_OVERRIDE(#id, id, table, &no_override)
 
-struct arm64_ftr_override id_aa64mmfr0_override;
-struct arm64_ftr_override id_aa64mmfr1_override;
-struct arm64_ftr_override id_aa64mmfr2_override;
-struct arm64_ftr_override id_aa64pfr0_override;
-struct arm64_ftr_override id_aa64pfr1_override;
-struct arm64_ftr_override id_aa64zfr0_override;
-struct arm64_ftr_override id_aa64smfr0_override;
-struct arm64_ftr_override id_aa64isar1_override;
-struct arm64_ftr_override id_aa64isar2_override;
-
-struct arm64_ftr_override arm64_sw_feature_override;
+struct arm64_ftr_override __read_mostly id_aa64mmfr0_override;
+struct arm64_ftr_override __read_mostly id_aa64mmfr1_override;
+struct arm64_ftr_override __read_mostly id_aa64mmfr2_override;
+struct arm64_ftr_override __read_mostly id_aa64pfr0_override;
+struct arm64_ftr_override __read_mostly id_aa64pfr1_override;
+struct arm64_ftr_override __read_mostly id_aa64zfr0_override;
+struct arm64_ftr_override __read_mostly id_aa64smfr0_override;
+struct arm64_ftr_override __read_mostly id_aa64isar1_override;
+struct arm64_ftr_override __read_mostly id_aa64isar2_override;
+
+struct arm64_ftr_override __read_mostly arm64_sw_feature_override;
 
 static const struct __ftr_reg_entry {
 	u32			sys_id;