linux-kernel - [PATCH v4 11/16] arm64/mm: Introduce a callback to flush the local context

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]

Date:   Wed, 14 Apr 2021 12:23:07 +0100
From:   Shameer Kolothum <shameerali.kolothum.thodi@...wei.com>
To:     <linux-arm-kernel@...ts.infradead.org>,
        <kvmarm@...ts.cs.columbia.edu>, <linux-kernel@...r.kernel.org>
CC:     <maz@...nel.org>, <will@...nel.org>, <catalin.marinas@....com>,
        <james.morse@....com>, <julien.thierry.kdev@...il.com>,
        <suzuki.poulose@....com>, <jean-philippe@...aro.org>,
        <julien@....org>, <linuxarm@...wei.com>
Subject: [PATCH v4 11/16] arm64/mm: Introduce a callback to flush the local context

From: Julien Grall <julien.grall@....com>

Flushing the local context will vary depending on the actual user
of the ASID allocator. Introduce a new callback to flush the local
context and move the call to flush local TLB in it.

Signed-off-by: Julien Grall <julien.grall@....com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@...wei.com>
---
 arch/arm64/mm/context.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c
index 901472a57b5d..ee446f7535a3 100644
--- a/arch/arm64/mm/context.c
+++ b/arch/arm64/mm/context.c
@@ -32,6 +32,8 @@ static struct asid_info
 	unsigned long		*pinned_map;
 	unsigned long		max_pinned_asids;
 	unsigned long		nr_pinned_asids;
+	/* Callback to locally flush the context. */
+	void			(*flush_cpu_ctxt_cb)(void);
 } asid_info;
 
 #define active_asid(info, cpu)	 (*per_cpu_ptr((info)->active, cpu))
@@ -245,8 +247,9 @@ static void asid_new_context(struct asid_info *info, atomic64_t *pasid,
 		atomic64_set(pasid, asid);
 	}
 
-	if (cpumask_test_and_clear_cpu(cpu, &info->flush_pending))
-		local_flush_tlb_all();
+	if (cpumask_test_and_clear_cpu(cpu, &info->flush_pending) &&
+	    info->flush_cpu_ctxt_cb)
+		info->flush_cpu_ctxt_cb();
 
 	atomic64_set(&active_asid(info, cpu), asid);
 	raw_spin_unlock_irqrestore(&info->lock, flags);
@@ -427,6 +430,11 @@ void cpu_do_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm)
 	post_ttbr_update_workaround();
 }
 
+static void asid_flush_cpu_ctxt(void)
+{
+	local_flush_tlb_all();
+}
+
 static int asids_update_limit(void)
 {
 	struct asid_info *info = &asid_info;
@@ -499,6 +507,7 @@ static int asids_init(void)
 
 	info->active = &active_asids;
 	info->reserved = &reserved_asids;
+	info->flush_cpu_ctxt_cb = asid_flush_cpu_ctxt;
 
 	/*
 	 * We cannot call set_reserved_asid_bits() here because CPU
-- 
2.17.1