[PATCH 2/3] arm64/boot: Move global CPU override variables out of BSS
Ard Biesheuvel
ardb+git at google.com
Sat May 3 04:21:41 PDT 2025
From: Ard Biesheuvel <ardb at kernel.org>
Accessing BSS will no longer be permitted form 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 <ardb at kernel.org>
---
arch/arm64/kernel/cpufeature.c | 22 ++++++++++----------
1 file changed, 11 insertions(+), 11 deletions(-)
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 9c4d6d552b25..4f7a8050ab85 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/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 __section(".data") id_aa64mmfr0_override;
+struct arm64_ftr_override __section(".data") id_aa64mmfr1_override;
+struct arm64_ftr_override __section(".data") id_aa64mmfr2_override;
+struct arm64_ftr_override __section(".data") id_aa64pfr0_override;
+struct arm64_ftr_override __section(".data") id_aa64pfr1_override;
+struct arm64_ftr_override __section(".data") id_aa64zfr0_override;
+struct arm64_ftr_override __section(".data") id_aa64smfr0_override;
+struct arm64_ftr_override __section(".data") id_aa64isar1_override;
+struct arm64_ftr_override __section(".data") id_aa64isar2_override;
+
+struct arm64_ftr_override __section(".data") arm64_sw_feature_override;
static const struct __ftr_reg_entry {
u32 sys_id;
--
2.49.0.906.g1f30a19c02-goog
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