public inbox for stable@vger.kernel.org
 help / color / mirror / Atom feed
From: "Maciej W. Rozycki" <macro@orcam.me.uk>
To: stable@vger.kernel.org
Cc: Stefan Wiehler <stefan.wiehler@nokia.com>,
	Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: [PATCH 5.10.y 2/5] mips: mm: Allocate tlb_vpn array atomically
Date: Fri, 10 Apr 2026 01:55:43 +0100	[thread overview]
Message-ID: <20260410005546.49873-2-macro@orcam.me.uk> (raw)
In-Reply-To: <20260410005546.49873-1-macro@orcam.me.uk>

From: Stefan Wiehler <stefan.wiehler@nokia.com>

commit 01cc50ea5167bb14117257ec084637abe9e5f691 upstream.

Found by DEBUG_ATOMIC_SLEEP:

  BUG: sleeping function called from invalid context at /include/linux/sched/mm.h:306
  in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
  preempt_count: 1, expected: 0
  RCU nest depth: 0, expected: 0
  no locks held by swapper/1/0.
  irq event stamp: 0
  hardirqs last  enabled at (0): [<0000000000000000>] 0x0
  hardirqs last disabled at (0): [<ffffffff801477fc>] copy_process+0x75c/0x1b68
  softirqs last  enabled at (0): [<ffffffff801477fc>] copy_process+0x75c/0x1b68
  softirqs last disabled at (0): [<0000000000000000>] 0x0
  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.6.119-d79e757675ec-fct #1
  Stack : 800000000290bad8 0000000000000000 0000000000000008 800000000290bae8
          800000000290bae8 800000000290bc78 0000000000000000 0000000000000000
          ffffffff80c80000 0000000000000001 ffffffff80d8dee8 ffffffff810d09c0
          784bb2a7ec10647d 0000000000000010 ffffffff80a6fd60 8000000001d8a9c0
          0000000000000000 0000000000000000 ffffffff80d90000 0000000000000000
          ffffffff80c9e0e8 0000000007ffffff 0000000000000cc0 0000000000000400
          ffffffffffffffff 0000000000000001 0000000000000002 ffffffffc0149ed8
          fffffffffffffffe 8000000002908000 800000000290bae0 ffffffff80a81b74
          ffffffff80129fb0 0000000000000000 0000000000000000 0000000000000000
          0000000000000000 0000000000000000 ffffffff80129fd0 0000000000000000
          ...
  Call Trace:
  [<ffffffff80129fd0>] show_stack+0x60/0x158
  [<ffffffff80a7f894>] dump_stack_lvl+0x88/0xbc
  [<ffffffff8018d3c8>] __might_resched+0x268/0x288
  [<ffffffff803648b0>] __kmem_cache_alloc_node+0x2e0/0x330
  [<ffffffff80302788>] __kmalloc+0x58/0xd0
  [<ffffffff80a81b74>] r4k_tlb_uniquify+0x7c/0x428
  [<ffffffff80143e8c>] tlb_init+0x7c/0x110
  [<ffffffff8012bdb4>] per_cpu_trap_init+0x16c/0x1d0
  [<ffffffff80133258>] start_secondary+0x28/0x128

Fixes: 231ac951faba ("MIPS: mm: kmalloc tlb_vpn array to avoid stack overflow")
Signed-off-by: Stefan Wiehler <stefan.wiehler@nokia.com>
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/mips/mm/tlb-r4k.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c
index 9da1fbe4a2d7..d9631f3b6460 100644
--- a/arch/mips/mm/tlb-r4k.c
+++ b/arch/mips/mm/tlb-r4k.c
@@ -528,7 +528,7 @@ static void __ref r4k_tlb_uniquify(void)
 
 	tlb_vpn_size = tlbsize * sizeof(*tlb_vpns);
 	tlb_vpns = (use_slab ?
-		    kmalloc(tlb_vpn_size, GFP_KERNEL) :
+		    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. */
-- 
2.20.1


  reply	other threads:[~2026-04-10  0:55 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-10  0:55 [PATCH 5.10.y 1/5] MIPS: mm: kmalloc tlb_vpn array to avoid stack overflow Maciej W. Rozycki
2026-04-10  0:55 ` Maciej W. Rozycki [this message]
2026-04-10  0:55 ` [PATCH 5.10.y 3/5] MIPS: Always record SEGBITS in cpu_data.vmbits Maciej W. Rozycki
2026-04-10  0:55 ` [PATCH 5.10.y 4/5] MIPS: mm: Suppress TLB uniquification on EHINV hardware Maciej W. Rozycki
2026-04-10  0:55 ` [PATCH 5.10.y 5/5] MIPS: mm: Rewrite TLB uniquification for the hidden bit feature Maciej W. Rozycki
2026-04-13  4:13 ` [PATCH 5.10.y 1-5/5] MIPS: mm: kmalloc tlb_vpn array to avoid stack overflow Sasha Levin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260410005546.49873-2-macro@orcam.me.uk \
    --to=macro@orcam.me.uk \
    --cc=gregkh@linuxfoundation.org \
    --cc=stable@vger.kernel.org \
    --cc=stefan.wiehler@nokia.com \
    --cc=tsbogend@alpha.franken.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox