linux-kernel - [PATCH v4 3/3] RISC-V: Issue a tlb page flush if possible

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190822075151.24838-4-atish.patra@wdc.com>
Date:   Thu, 22 Aug 2019 00:51:51 -0700
From:   Atish Patra <atish.patra@....com>
To:     linux-kernel@...r.kernel.org
Cc:     Atish Patra <atish.patra@....com>,
        Albert Ou <aou@...s.berkeley.edu>,
        linux-riscv@...ts.infradead.org,
        Palmer Dabbelt <palmer@...ive.com>,
        Paul Walmsley <paul.walmsley@...ive.com>,
        Christoph Hellwig <hch@....de>, Anup Patel <Anup.Patel@....com>
Subject: [PATCH v4 3/3] RISC-V: Issue a tlb page flush if possible

If tlbflush request is for page only, there is no need to do a
complete local tlb shootdown.

Just do a local tlb flush for the given address.

Signed-off-by: Atish Patra <atish.patra@....com>
---
 arch/riscv/mm/tlbflush.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
index 8172fbf46123..b1c04751bcf1 100644
--- a/arch/riscv/mm/tlbflush.c
+++ b/arch/riscv/mm/tlbflush.c
@@ -27,7 +27,10 @@ static void __sbi_tlb_flush_range(struct cpumask *cmask, unsigned long start,
 
 	if (cpumask_any_but(cmask, cpuid) >= nr_cpu_ids) {
 		/* local cpu is the only cpu present in cpumask */
-		local_flush_tlb_all();
+		if (size <= PAGE_SIZE)
+			local_flush_tlb_page(start);
+		else
+			local_flush_tlb_all();
 	} else {
 		riscv_cpuid_to_hartid_mask(cmask, &hmask);
 		sbi_remote_sfence_vma(cpumask_bits(&hmask), start, size);
-- 
2.21.0