riscv: mm: Fix incorrect ASID argument when flushing TLB

Currently, we pass the CONTEXTID instead of the ASID to the TLB flush
function. We should only take the ASID field to prevent from touching
the reserved bit field.

Fixes: 3f1e782998cd ("riscv: add ASID-based tlbflushing methods")
Signed-off-by: Dylan Jhong <dylan@andestech.com>
Reviewed-by: Sergey Matyukevich <sergey.matyukevich@syntacore.com>
Link: https://lore.kernel.org/r/20230313034906.2401730-1-dylan@andestech.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h
index 801019381dea3fec53f50fe443fb350c3ab92c43..a09196f8de688ea90123bb74fc21e080cde19f22 100644 (file)
--- a/arch/riscv/include/asm/tlbflush.h
+++ b/arch/riscv/include/asm/tlbflush.h
@@ -12,6 +12,8 @@
 #include <asm/errata_list.h>
 
 #ifdef CONFIG_MMU
+extern unsigned long asid_mask;
+
 static inline void local_flush_tlb_all(void)
 {
        __asm__ __volatile__ ("sfence.vma" : : : "memory");

diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
index 0f784e3d307bbce4afaaa3a377b1f8d2d54e35bd..12e22e7330e7bd2f0feee680b143c407473f0a81 100644 (file)
--- a/arch/riscv/mm/context.c
+++ b/arch/riscv/mm/context.c
@@ -22,7 +22,7 @@ DEFINE_STATIC_KEY_FALSE(use_asid_allocator);
 
 static unsigned long asid_bits;
 static unsigned long num_asids;
-static unsigned long asid_mask;
+unsigned long asid_mask;
 
 static atomic_long_t current_version;
 

diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
index 37ed760d007c3eef9c302adda361cd4ad7d1db9d..ef701fa83f3685c6d497ccda59086e7b9f0da20b 100644 (file)
--- a/arch/riscv/mm/tlbflush.c
+++ b/arch/riscv/mm/tlbflush.c
@@ -42,7 +42,7 @@ static void __sbi_tlb_flush_range(struct mm_struct *mm, unsigned long start,
        /* check if the tlbflush needs to be sent to other CPUs */
        broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
        if (static_branch_unlikely(&use_asid_allocator)) {
-               unsigned long asid = atomic_long_read(&mm->context.id);
+               unsigned long asid = atomic_long_read(&mm->context.id) & asid_mask;
 
                if (broadcast) {
                        sbi_remote_sfence_vma_asid(cmask, start, size, asid);