Commit 3033b2b1e394 for kernel

commit 3033b2b1e3949274f33a140e2a97571b5a307298
Author: Zishun Yi <vulab@iscas.ac.cn>
Date:   Mon Mar 23 00:00:22 2026 +0800

    riscv: Reset pmm when PR_TAGGED_ADDR_ENABLE is not set

    In set_tagged_addr_ctrl(), when PR_TAGGED_ADDR_ENABLE is not set, pmlen
    is correctly set to 0, but it forgets to reset pmm. This results in the
    CPU pmm state not corresponding to the software pmlen state.

    Fix this by resetting pmm along with pmlen.

    Fixes: 2e1743085887 ("riscv: Add support for the tagged address ABI")
    Signed-off-by: Zishun Yi <vulab@iscas.ac.cn>
    Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
    Link: https://patch.msgid.link/20260322160022.21908-1-vulab@iscas.ac.cn
    Signed-off-by: Paul Walmsley <pjw@kernel.org>

diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index aacb23978f93..5957effab57c 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -347,8 +347,10 @@ long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg)
 	if (arg & PR_TAGGED_ADDR_ENABLE && (tagged_addr_disabled || !pmlen))
 		return -EINVAL;

-	if (!(arg & PR_TAGGED_ADDR_ENABLE))
+	if (!(arg & PR_TAGGED_ADDR_ENABLE)) {
 		pmlen = PMLEN_0;
+		pmm = ENVCFG_PMM_PMLEN_0;
+	}

 	if (mmap_write_lock_killable(mm))
 		return -EINTR;