Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
MIPS: mm: kmalloc tlb_vpn array to avoid stack overflow
Owing to Config4.MMUSizeExt and VTLB/FTLB MMU features later MIPSr2+
cores can have more than 64 TLB entries. Therefore allocate an array
for uniquification instead of placing too an small array on the stack.
Fixes: 35ad7e181541 ("MIPS: mm: tlb-r4k: Uniquify TLB entries on init")
Co-developed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Cc: stable@vger.kernel.org # v6.17+: 9f048fa48740: MIPS: mm: Prevent a TLB shutdown on initial uniquification
Cc: stable@vger.kernel.org # v6.17+
Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Tested-by: Klara Modin <klarasmodin@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
+16
-2
+16
-2
arch/mips/mm/tlb-r4k.c
+16
-2
arch/mips/mm/tlb-r4k.c
···
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/smp.h>
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+
#include <linux/memblock.h>
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#include <linux/mm.h>
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#include <linux/hugetlb.h>
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#include <linux/export.h>
···
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* Initialise all TLB entries with unique values that do not clash with
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* what we have been handed over and what we'll be using ourselves.
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*/
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-
static void r4k_tlb_uniquify(void)
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+
static void __ref r4k_tlb_uniquify(void)
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{
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-
unsigned long tlb_vpns[1 << MIPS_CONF1_TLBS_SIZE];
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int tlbsize = current_cpu_data.tlbsize;
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+
bool use_slab = slab_is_available();
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int start = num_wired_entries();
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phys_addr_t tlb_vpn_size;
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unsigned long *tlb_vpns;
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unsigned long vpn_mask;
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int cnt, ent, idx, i;
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vpn_mask = GENMASK(cpu_vmbits - 1, 13);
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vpn_mask |= IS_ENABLED(CONFIG_64BIT) ? 3ULL << 62 : 1 << 31;
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+
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tlb_vpn_size = tlbsize * sizeof(*tlb_vpns);
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tlb_vpns = (use_slab ?
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kmalloc(tlb_vpn_size, GFP_KERNEL) :
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memblock_alloc_raw(tlb_vpn_size, sizeof(*tlb_vpns)));
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if (WARN_ON(!tlb_vpns))
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return; /* Pray local_flush_tlb_all() is good enough. */
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htw_stop();
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···
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tlbw_use_hazard();
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htw_start();
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flush_micro_tlb();
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+
if (use_slab)
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kfree(tlb_vpns);
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else
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memblock_free(tlb_vpns, tlb_vpn_size);
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}
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/*