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authorPaolo Bonzini <pbonzini@redhat.com>2023-02-15 12:33:28 -0500
committerPaolo Bonzini <pbonzini@redhat.com>2023-02-15 12:33:28 -0500
commit33436335e93a1788a58443fc99c5ab320ce4b9d9 (patch)
treed92f88768c8dbd00f8b65164f47a8a091768b95a /rust/kernel/print.rs
parent27b025ebb0f6092d5c0a88de2ab73545bc1c496e (diff)
parentc39cea6f38eefe356d64d0bc1e1f2267e282cdd3 (diff)
Merge tag 'kvm-riscv-6.3-1' of https://github.com/kvm-riscv/linux into HEAD
KVM/riscv changes for 6.3 - Fix wrong usage of PGDIR_SIZE to check page sizes - Fix privilege mode setting in kvm_riscv_vcpu_trap_redirect() - Redirect illegal instruction traps to guest - SBI PMU support for guest
Diffstat (limited to 'rust/kernel/print.rs')
-rw-r--r--rust/kernel/print.rs29
1 files changed, 18 insertions, 11 deletions
diff --git a/rust/kernel/print.rs b/rust/kernel/print.rs
index 29bf9c2e8aee..30103325696d 100644
--- a/rust/kernel/print.rs
+++ b/rust/kernel/print.rs
@@ -142,17 +142,24 @@ pub fn call_printk_cont(args: fmt::Arguments<'_>) {
macro_rules! print_macro (
// The non-continuation cases (most of them, e.g. `INFO`).
($format_string:path, false, $($arg:tt)+) => (
- // SAFETY: This hidden macro should only be called by the documented
- // printing macros which ensure the format string is one of the fixed
- // ones. All `__LOG_PREFIX`s are null-terminated as they are generated
- // by the `module!` proc macro or fixed values defined in a kernel
- // crate.
- unsafe {
- $crate::print::call_printk(
- &$format_string,
- crate::__LOG_PREFIX,
- format_args!($($arg)+),
- );
+ // To remain sound, `arg`s must be expanded outside the `unsafe` block.
+ // Typically one would use a `let` binding for that; however, `format_args!`
+ // takes borrows on the arguments, but does not extend the scope of temporaries.
+ // Therefore, a `match` expression is used to keep them around, since
+ // the scrutinee is kept until the end of the `match`.
+ match format_args!($($arg)+) {
+ // SAFETY: This hidden macro should only be called by the documented
+ // printing macros which ensure the format string is one of the fixed
+ // ones. All `__LOG_PREFIX`s are null-terminated as they are generated
+ // by the `module!` proc macro or fixed values defined in a kernel
+ // crate.
+ args => unsafe {
+ $crate::print::call_printk(
+ &$format_string,
+ crate::__LOG_PREFIX,
+ args,
+ );
+ }
}
);