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* [PATCH 0/3] MIPS: Avoid a TLB shutdown induced by a hidden TLB entry bit
@ 2026-03-27 18:57 Maciej W. Rozycki
  2026-03-27 18:57 ` [PATCH 1/3] MIPS: Always record SEGBITS in cpu_data.vmbits Maciej W. Rozycki
                   ` (3 more replies)
  0 siblings, 4 replies; 5+ messages in thread
From: Maciej W. Rozycki @ 2026-03-27 18:57 UTC (permalink / raw)
  To: Thomas Bogendoerfer, Gregory CLEMENT, Thomas Huth,
	Philippe Mathieu-Daudé, Keguang Zhang, Jiaxun Yang
  Cc: Waldemar Brodkorb, linux-mips, linux-kernel

Hi,

 This is a reimplementation of initial TLB entry uniquification so as to 
address an issue with processors that implement a hidden TLB entry bit 
triggered by commit 9f048fa48740 ("MIPS: mm: Prevent a TLB shutdown on 
initial uniquification") for platforms that hand the TLB over unchanged 
from reset.

 This has been verified across the following systems:

- DECstation 5000/150, R4000SC MIPS III CPU, SEGBITS == 40, 48-entry TLB, 
  32-bit kernel,

- Broadcom BCM91250A, BCM1250 MIPS64 CPU, SEGBITS == 44, 64-entry TLB, 
  64-bit kernel,

- MIPS Malta, 74Kf MIPS32r2 CPU, SEGBITS == 31, 64-entry TLB, 32-bit 
  kernel.

A debug change was used to verify the TLB is initialised as expected.

 See individual commit descriptions for details.

 I consider this code ready to use, but given the diversity of TLB designs 
with MIPS architecture processors I will appreciate verification across 
various actual hardware, particularly in preparation for backporting, as 
this addresses a serious regression for a subset of systems.

 Please apply otherwise.  Thank you for patience waiting for this fix.

  Maciej

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2026-03-27 21:27 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-03-27 18:57 [PATCH 0/3] MIPS: Avoid a TLB shutdown induced by a hidden TLB entry bit Maciej W. Rozycki
2026-03-27 18:57 ` [PATCH 1/3] MIPS: Always record SEGBITS in cpu_data.vmbits Maciej W. Rozycki
2026-03-27 18:57 ` [PATCH 2/3] MIPS: mm: Suppress TLB uniquification on EHINV hardware Maciej W. Rozycki
2026-03-27 18:57 ` [PATCH 3/3] MIPS: mm: Rewrite TLB uniquification for the hidden bit feature Maciej W. Rozycki
2026-03-27 21:20 ` [PATCH 0/3] MIPS: Avoid a TLB shutdown induced by a hidden TLB entry bit Waldemar Brodkorb

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