+++ /dev/null
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Hauke Mehrtens <hauke@hauke-m.de>
-Date: Mon, 15 Dec 2025 01:45:07 +0100
-Subject: Revert "MIPS: mm: kmalloc tlb_vpn array to avoid stack overflow"
-
-This reverts commit 63a93d1cd6077d79735f804f5a4957bfb240280c.
----
- arch/mips/mm/tlb-r4k.c | 18 ++----------------
- 1 file changed, 2 insertions(+), 16 deletions(-)
-
---- a/arch/mips/mm/tlb-r4k.c
-+++ b/arch/mips/mm/tlb-r4k.c
-@@ -12,7 +12,6 @@
- #include <linux/init.h>
- #include <linux/sched.h>
- #include <linux/smp.h>
--#include <linux/memblock.h>
- #include <linux/mm.h>
- #include <linux/hugetlb.h>
- #include <linux/export.h>
-@@ -523,26 +522,17 @@ static int r4k_vpn_cmp(const void *a, co
- * Initialise all TLB entries with unique values that do not clash with
- * what we have been handed over and what we'll be using ourselves.
- */
--static void __ref r4k_tlb_uniquify(void)
-+static void r4k_tlb_uniquify(void)
- {
-+ unsigned long tlb_vpns[1 << MIPS_CONF1_TLBS_SIZE];
- int tlbsize = current_cpu_data.tlbsize;
-- bool use_slab = slab_is_available();
- int start = num_wired_entries();
-- phys_addr_t tlb_vpn_size;
-- unsigned long *tlb_vpns;
- unsigned long vpn_mask;
- int cnt, ent, idx, i;
-
- vpn_mask = GENMASK(cpu_vmbits - 1, 13);
- vpn_mask |= IS_ENABLED(CONFIG_64BIT) ? 3ULL << 62 : 1 << 31;
-
-- tlb_vpn_size = tlbsize * sizeof(*tlb_vpns);
-- tlb_vpns = (use_slab ?
-- kmalloc(tlb_vpn_size, GFP_ATOMIC) :
-- memblock_alloc_raw(tlb_vpn_size, sizeof(*tlb_vpns)));
-- if (WARN_ON(!tlb_vpns))
-- return; /* Pray local_flush_tlb_all() is good enough. */
--
- htw_stop();
-
- for (i = start, cnt = 0; i < tlbsize; i++, cnt++) {
-@@ -595,10 +585,6 @@ static void __ref r4k_tlb_uniquify(void)
- tlbw_use_hazard();
- htw_start();
- flush_micro_tlb();
-- if (use_slab)
-- kfree(tlb_vpns);
-- else
-- memblock_free(tlb_vpns, tlb_vpn_size);
- }
-
- /*
+++ /dev/null
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Hauke Mehrtens <hauke@hauke-m.de>
-Date: Mon, 15 Dec 2025 01:45:20 +0100
-Subject: Revert "MIPS: mm: Prevent a TLB shutdown on initial uniquification"
-
-This reverts commit 135178e90aa43ad949534e1d6e376c4034942caa.
----
- arch/mips/mm/tlb-r4k.c | 100 +++++++++++++++--------------------------
- 1 file changed, 37 insertions(+), 63 deletions(-)
-
---- a/arch/mips/mm/tlb-r4k.c
-+++ b/arch/mips/mm/tlb-r4k.c
-@@ -15,7 +15,6 @@
- #include <linux/mm.h>
- #include <linux/hugetlb.h>
- #include <linux/export.h>
--#include <linux/sort.h>
-
- #include <asm/cpu.h>
- #include <asm/cpu-type.h>
-@@ -509,79 +508,55 @@ static int __init set_ntlb(char *str)
-
- __setup("ntlb=", set_ntlb);
-
--
--/* Comparison function for EntryHi VPN fields. */
--static int r4k_vpn_cmp(const void *a, const void *b)
--{
-- long v = *(unsigned long *)a - *(unsigned long *)b;
-- int s = sizeof(long) > sizeof(int) ? sizeof(long) * 8 - 1: 0;
-- return s ? (v != 0) | v >> s : v;
--}
--
--/*
-- * Initialise all TLB entries with unique values that do not clash with
-- * what we have been handed over and what we'll be using ourselves.
-- */
-+/* Initialise all TLB entries with unique values */
- static void r4k_tlb_uniquify(void)
- {
-- unsigned long tlb_vpns[1 << MIPS_CONF1_TLBS_SIZE];
-- int tlbsize = current_cpu_data.tlbsize;
-- int start = num_wired_entries();
-- unsigned long vpn_mask;
-- int cnt, ent, idx, i;
--
-- vpn_mask = GENMASK(cpu_vmbits - 1, 13);
-- vpn_mask |= IS_ENABLED(CONFIG_64BIT) ? 3ULL << 62 : 1 << 31;
-+ int entry = num_wired_entries();
-
- htw_stop();
-+ write_c0_entrylo0(0);
-+ write_c0_entrylo1(0);
-
-- for (i = start, cnt = 0; i < tlbsize; i++, cnt++) {
-- unsigned long vpn;
-+ while (entry < current_cpu_data.tlbsize) {
-+ unsigned long asid_mask = cpu_asid_mask(¤t_cpu_data);
-+ unsigned long asid = 0;
-+ int idx;
-
-- write_c0_index(i);
-- mtc0_tlbr_hazard();
-- tlb_read();
-- tlb_read_hazard();
-- vpn = read_c0_entryhi();
-- vpn &= vpn_mask & PAGE_MASK;
-- tlb_vpns[cnt] = vpn;
-+ /* Skip wired MMID to make ginvt_mmid work */
-+ if (cpu_has_mmid)
-+ asid = MMID_KERNEL_WIRED + 1;
-
-- /* Prevent any large pages from overlapping regular ones. */
-- write_c0_pagemask(read_c0_pagemask() & PM_DEFAULT_MASK);
-+ /* Check for match before using UNIQUE_ENTRYHI */
-+ do {
-+ if (cpu_has_mmid) {
-+ write_c0_memorymapid(asid);
-+ write_c0_entryhi(UNIQUE_ENTRYHI(entry));
-+ } else {
-+ write_c0_entryhi(UNIQUE_ENTRYHI(entry) | asid);
-+ }
-+ mtc0_tlbw_hazard();
-+ tlb_probe();
-+ tlb_probe_hazard();
-+ idx = read_c0_index();
-+ /* No match or match is on current entry */
-+ if (idx < 0 || idx == entry)
-+ break;
-+ /*
-+ * If we hit a match, we need to try again with
-+ * a different ASID.
-+ */
-+ asid++;
-+ } while (asid < asid_mask);
-+
-+ if (idx >= 0 && idx != entry)
-+ panic("Unable to uniquify TLB entry %d", idx);
-+
-+ write_c0_index(entry);
- mtc0_tlbw_hazard();
- tlb_write_indexed();
-- tlbw_use_hazard();
-+ entry++;
- }
-
-- sort(tlb_vpns, cnt, sizeof(tlb_vpns[0]), r4k_vpn_cmp, NULL);
--
-- write_c0_pagemask(PM_DEFAULT_MASK);
-- write_c0_entrylo0(0);
-- write_c0_entrylo1(0);
--
-- idx = 0;
-- ent = tlbsize;
-- for (i = start; i < tlbsize; i++)
-- while (1) {
-- unsigned long entryhi, vpn;
--
-- entryhi = UNIQUE_ENTRYHI(ent);
-- vpn = entryhi & vpn_mask & PAGE_MASK;
--
-- if (idx >= cnt || vpn < tlb_vpns[idx]) {
-- write_c0_entryhi(entryhi);
-- write_c0_index(i);
-- mtc0_tlbw_hazard();
-- tlb_write_indexed();
-- ent++;
-- break;
-- } else if (vpn == tlb_vpns[idx]) {
-- ent++;
-- } else {
-- idx++;
-- }
-- }
--
- tlbw_use_hazard();
- htw_start();
- flush_micro_tlb();
-@@ -627,7 +602,6 @@ static void r4k_tlb_configure(void)
-
- /* From this point on the ARC firmware is dead. */
- r4k_tlb_uniquify();
-- local_flush_tlb_all();
-
- /* Did I tell you that ARC SUCKS? */
- }
projects / thirdparty / openwrt.git / commitdiff
