On Fri, 17 Jun 2022 15:56:31 +0200, Péter Ujfalusi wrote: > > Hi Takashi, > > On 17/06/2022 15:29, Takashi Iwai wrote: > > Hi, > > Try #2, first mail did not made it through, I think. > > > can anyone have an AMD onboard audio device and/or AMD HDMI/DP output > > for testing a patch below with 5.18.x or 5.19-rc kernels? It's a > > pending fix (for 5.18+), but currently it can't be verified whether it > > causes a regression on the actual audio I/O (while it fixes the kernel > > crash). > > > > If the generic allocator still doesn't work as expected here, it > > should show some audio stuttering or such effect. > > But the fallback was needed for some machines using SOF to be able to > load the firmware... > like this: > https://github.com/thesofproject/linux/issues/3609 The bug isn't about the fallback of SG buffer we've already resolved, but rather about the continuous WC page allocations that happen for the CORB/RIRB or the position buffer on some devices like AMD. The Intel HD-audio doesn't hit the problem. Takashi > > > > > > > Thanks! > > > > Takashi > > > > -- 8< -- > > From: Takashi Iwai <tiwai@xxxxxxx> > > Subject: [PATCH] ALSA: memalloc: Drop x86-specific hack for WC allocations > > > > The recent report for a crash on Haswell machines implied that the > > x86-specific (rather hackish) implementation for write-cache memory > > buffer allocation in ALSA core is buggy with the recent kernel in some > > corner cases. This patch drops the x86-specific implementation and > > uses the standard dma_alloc_wc() & co generically for avoiding the bug > > and also for simplification. > > > > BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=216112 > > Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> > > --- > > sound/core/memalloc.c | 23 +---------------------- > > 1 file changed, 1 insertion(+), 22 deletions(-) > > > > diff --git a/sound/core/memalloc.c b/sound/core/memalloc.c > > index 15dc7160ba34..8cfdaee77905 100644 > > --- a/sound/core/memalloc.c > > +++ b/sound/core/memalloc.c > > @@ -431,33 +431,17 @@ static const struct snd_malloc_ops snd_dma_iram_ops = { > > */ > > static void *snd_dma_dev_alloc(struct snd_dma_buffer *dmab, size_t size) > > { > > - void *p; > > - > > - p = dma_alloc_coherent(dmab->dev.dev, size, &dmab->addr, DEFAULT_GFP); > > -#ifdef CONFIG_X86 > > - if (p && dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC) > > - set_memory_wc((unsigned long)p, PAGE_ALIGN(size) >> PAGE_SHIFT); > > -#endif > > - return p; > > + return dma_alloc_coherent(dmab->dev.dev, size, &dmab->addr, DEFAULT_GFP); > > } > > > > static void snd_dma_dev_free(struct snd_dma_buffer *dmab) > > { > > -#ifdef CONFIG_X86 > > - if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC) > > - set_memory_wb((unsigned long)dmab->area, > > - PAGE_ALIGN(dmab->bytes) >> PAGE_SHIFT); > > -#endif > > dma_free_coherent(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr); > > } > > > > static int snd_dma_dev_mmap(struct snd_dma_buffer *dmab, > > struct vm_area_struct *area) > > { > > -#ifdef CONFIG_X86 > > - if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC) > > - area->vm_page_prot = pgprot_writecombine(area->vm_page_prot); > > -#endif > > return dma_mmap_coherent(dmab->dev.dev, area, > > dmab->area, dmab->addr, dmab->bytes); > > } > > @@ -471,10 +455,6 @@ static const struct snd_malloc_ops snd_dma_dev_ops = { > > /* > > * Write-combined pages > > */ > > -#ifdef CONFIG_X86 > > -/* On x86, share the same ops as the standard dev ops */ > > -#define snd_dma_wc_ops snd_dma_dev_ops > > -#else /* CONFIG_X86 */ > > static void *snd_dma_wc_alloc(struct snd_dma_buffer *dmab, size_t size) > > { > > return dma_alloc_wc(dmab->dev.dev, size, &dmab->addr, DEFAULT_GFP); > > @@ -497,7 +477,6 @@ static const struct snd_malloc_ops snd_dma_wc_ops = { > > .free = snd_dma_wc_free, > > .mmap = snd_dma_wc_mmap, > > }; > > -#endif /* CONFIG_X86 */ > > > > #ifdef CONFIG_SND_DMA_SGBUF > > static void *snd_dma_sg_fallback_alloc(struct snd_dma_buffer *dmab, size_t size); > > -- > Péter >
