Re: [PATCH 18/21] ARM: drop SMP support for ARM11MPCore

2023-03-31 Thread Catalin Marinas
On Mon, Mar 27, 2023 at 02:13:14PM +0200, Arnd Bergmann wrote: > From: Arnd Bergmann > > The cache management operations for noncoherent DMA on ARMv6 work > in two different ways: > > * When CONFIG_DMA_CACHE_RWFO is set, speculative prefetches on in-flight >DMA buffers lead to data corrupti

Re: [PATCH 18/21] ARM: drop SMP support for ARM11MPCore

2023-03-30 Thread Neil Armstrong
Le 30/03/2023 à 12:03, Arnd Bergmann a écrit : On Thu, Mar 30, 2023, at 09:48, Neil Armstrong wrote: On 27/03/2023 14:13, Arnd Bergmann wrote: From: Arnd Bergmann The cache management operations for noncoherent DMA on ARMv6 work in two different ways: * When CONFIG_DMA_CACHE_RWFO is set,

Re: [PATCH 18/21] ARM: drop SMP support for ARM11MPCore

2023-03-30 Thread Neil Armstrong
On 27/03/2023 14:13, Arnd Bergmann wrote: From: Arnd Bergmann The cache management operations for noncoherent DMA on ARMv6 work in two different ways: * When CONFIG_DMA_CACHE_RWFO is set, speculative prefetches on in-flight DMA buffers lead to data corruption when the prefetched data is

Re: [PATCH 18/21] ARM: drop SMP support for ARM11MPCore

2023-03-30 Thread Ard Biesheuvel
On Mon, 27 Mar 2023 at 14:18, Arnd Bergmann wrote: > > From: Arnd Bergmann > > The cache management operations for noncoherent DMA on ARMv6 work > in two different ways: > > * When CONFIG_DMA_CACHE_RWFO is set, speculative prefetches on in-flight >DMA buffers lead to data corruption when the

Re: [PATCH 18/21] ARM: drop SMP support for ARM11MPCore

2023-03-30 Thread Arnd Bergmann
On Thu, Mar 30, 2023, at 09:48, Neil Armstrong wrote: > On 27/03/2023 14:13, Arnd Bergmann wrote: >> From: Arnd Bergmann >> >> The cache management operations for noncoherent DMA on ARMv6 work >> in two different ways: >> >> * When CONFIG_DMA_CACHE_RWFO is set, speculative prefetches on in-fli

Re: [PATCH 18/21] ARM: drop SMP support for ARM11MPCore

2023-03-30 Thread Linus Walleij
On Mon, Mar 27, 2023 at 2:16 PM Arnd Bergmann wrote: > From: Arnd Bergmann > > The cache management operations for noncoherent DMA on ARMv6 work > in two different ways: > > * When CONFIG_DMA_CACHE_RWFO is set, speculative prefetches on in-flight >DMA buffers lead to data corruption when th

[PATCH 18/21] ARM: drop SMP support for ARM11MPCore

2023-03-27 Thread Arnd Bergmann
From: Arnd Bergmann The cache management operations for noncoherent DMA on ARMv6 work in two different ways: * When CONFIG_DMA_CACHE_RWFO is set, speculative prefetches on in-flight DMA buffers lead to data corruption when the prefetched data is written back on top of data from the device