From: Claudiu Beznea Date: Mon, 16 Mar 2026 13:32:46 +0000 (+0200) Subject: dmaengine: sh: rz-dmac: Move CHCTRL updates under spinlock X-Git-Tag: v7.0-rc6~3^2~4 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=89a8567d84bde88cb7cdbbac2ab2299c4f991490;p=thirdparty%2Flinux.git dmaengine: sh: rz-dmac: Move CHCTRL updates under spinlock Both rz_dmac_disable_hw() and rz_dmac_irq_handle_channel() update the CHCTRL register. To avoid concurrency issues when configuring functionalities exposed by this registers, take the virtual channel lock. All other CHCTRL updates were already protected by the same lock. Previously, rz_dmac_disable_hw() disabled and re-enabled local IRQs, before accessing CHCTRL registers but this does not ensure race-free access. Remove the local IRQ disable/enable code as well. Fixes: 5000d37042a6 ("dmaengine: sh: Add DMAC driver for RZ/G2L SoC") Cc: stable@vger.kernel.org Reviewed-by: Biju Das Reviewed-by: Frank Li Signed-off-by: Claudiu Beznea Link: https://patch.msgid.link/20260316133252.240348-3-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Vinod Koul --- diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 089e1ab29159..f30bdf69c740 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -297,13 +297,10 @@ static void rz_dmac_disable_hw(struct rz_dmac_chan *channel) { struct dma_chan *chan = &channel->vc.chan; struct rz_dmac *dmac = to_rz_dmac(chan->device); - unsigned long flags; dev_dbg(dmac->dev, "%s channel %d\n", __func__, channel->index); - local_irq_save(flags); rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1); - local_irq_restore(flags); } static void rz_dmac_set_dmars_register(struct rz_dmac *dmac, int nr, u32 dmars) @@ -568,8 +565,8 @@ static int rz_dmac_terminate_all(struct dma_chan *chan) unsigned int i; LIST_HEAD(head); - rz_dmac_disable_hw(channel); spin_lock_irqsave(&channel->vc.lock, flags); + rz_dmac_disable_hw(channel); for (i = 0; i < DMAC_NR_LMDESC; i++) lmdesc[i].header = 0; @@ -706,7 +703,9 @@ static void rz_dmac_irq_handle_channel(struct rz_dmac_chan *channel) if (chstat & CHSTAT_ER) { dev_err(dmac->dev, "DMAC err CHSTAT_%d = %08X\n", channel->index, chstat); - rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1); + + scoped_guard(spinlock_irqsave, &channel->vc.lock) + rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1); goto done; }