| Message ID | cover.1662455798.git.rahul.singh@arm.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | xen/arm: smmuv3: Merge Linux fixes to Xen | expand |
Hi Rahul, > On 6 Sep 2022, at 10:55, Rahul Singh <Rahul.Singh@arm.com> wrote: > > From: Zhou Wang <wangzhou1@hisilicon.com> > > Backport Linux commit a76a37777f2c. Introduce __iomb() in the smmu-v3.c > file with other Linux compatibility definitions. > > Reading the 'prod' MMIO register in order to determine whether or > not there is valid data beyond 'cons' for a given queue does not > provide sufficient dependency ordering, as the resulting access is > address dependent only on 'cons' and can therefore be speculated > ahead of time, potentially allowing stale data to be read by the > CPU. > > Use readl() instead of readl_relaxed() when updating the shadow copy > of the 'prod' pointer, so that all speculated memory reads from the > corresponding queue can occur only from valid slots. > > Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com> > Link: https://lore.kernel.org/r/1601281922-117296-1-git-send-email-wangzhou1@hisilicon.com > [will: Use readl() instead of explicit barrier. Update 'cons' side to match.] > Signed-off-by: Will Deacon <will@kernel.org> > Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git a76a37777f2c > Signed-off-by: Rahul Singh <rahul.singh@arm.com> Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com> Cheers Bertrand > --- > Changes in v4: > - rename iomb() to __iomb() > Changes in v3: > - rename __iomb() to iomb() and also move it from common file to > smmu-v3.c file > Changes in v2: > - fix commit msg > - add __iomb changes also from the origin patch > --- > xen/drivers/passthrough/arm/smmu-v3.c | 13 +++++++++++-- > 1 file changed, 11 insertions(+), 2 deletions(-) > > diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c > index 64d39bb4d3..229b9a4b0d 100644 > --- a/xen/drivers/passthrough/arm/smmu-v3.c > +++ b/xen/drivers/passthrough/arm/smmu-v3.c > @@ -107,6 +107,8 @@ typedef paddr_t dma_addr_t; > typedef paddr_t phys_addr_t; > typedef unsigned int gfp_t; > > +#define __iomb() dmb(osh) > + > #define platform_device device > > #define GFP_KERNEL 0 > @@ -951,7 +953,7 @@ static void queue_sync_cons_out(struct arm_smmu_queue *q) > * Ensure that all CPU accesses (reads and writes) to the queue > * are complete before we update the cons pointer. > */ > - mb(); > + __iomb(); > writel_relaxed(q->llq.cons, q->cons_reg); > } > > @@ -963,8 +965,15 @@ static void queue_inc_cons(struct arm_smmu_ll_queue *q) > > static int queue_sync_prod_in(struct arm_smmu_queue *q) > { > + u32 prod; > int ret = 0; > - u32 prod = readl_relaxed(q->prod_reg); > + > + /* > + * We can't use the _relaxed() variant here, as we must prevent > + * speculative reads of the queue before we have determined that > + * prod has indeed moved. > + */ > + prod = readl(q->prod_reg); > > if (Q_OVF(prod) != Q_OVF(q->llq.prod)) > ret = -EOVERFLOW; > -- > 2.25.1 >
Hi, On 06/09/2022 10:55, Rahul Singh wrote: > This patch series merge the applicable Linux fixes to Xen. > > Bixuan Cui (1): > xen/arm: smmuv3: Change *array into *const array > > Christophe JAILLET (1): > xen/arm: smmuv3: Avoid open coded arithmetic in memory allocation > > Gustavo A. R. Silva (1): > xen/arm: smmuv3: Fix fall-through warning for Clang > > Jean-Philippe Brucker (2): > xen/arm: smmuv3: Fix endianness annotations > xen/arm: smmuv3: Move definitions to a header > > Robin Murphy (1): > xen/arm: smmuv3: Remove the page 1 fixup > > Zenghui Yu (2): > xen/arm: smmuv3: Fix l1 stream table size in the error message > xen/arm: smmuv3: Remove the unused fields for PREFETCH_CONFIG command > > Zhen Lei (1): > xen/arm: smmuv3: Remove unnecessary oom message > > Zhou Wang (1): > xen/arm: smmuv3: Ensure queue is read after updating prod pointer I didn't get the full series in my inbox. So I used the branch Bertrand pushed on gitlab [1]. That said, I had to tweak all the commit messages to remove the tags Issue-Id and Change-Id. I have also added Bertrand's reviewed-by tag on patch #3. It is now fully committed. Cheers, [1] https://gitlab.com/xen-project/people/bmarquis/xen-arm-poc/-/tree/temp/smmuv3-fixes > > xen/drivers/passthrough/arm/smmu-v3.c | 741 ++------------------------ > xen/drivers/passthrough/arm/smmu-v3.h | 672 +++++++++++++++++++++++ > 2 files changed, 708 insertions(+), 705 deletions(-) > create mode 100644 xen/drivers/passthrough/arm/smmu-v3.h >
Hi Julien, > On 6 Sep 2022, at 5:49 pm, Julien Grall <julien@xen.org> wrote: > > Hi, > > On 06/09/2022 10:55, Rahul Singh wrote: >> This patch series merge the applicable Linux fixes to Xen. >> Bixuan Cui (1): >> xen/arm: smmuv3: Change *array into *const array >> Christophe JAILLET (1): >> xen/arm: smmuv3: Avoid open coded arithmetic in memory allocation >> Gustavo A. R. Silva (1): >> xen/arm: smmuv3: Fix fall-through warning for Clang >> Jean-Philippe Brucker (2): >> xen/arm: smmuv3: Fix endianness annotations >> xen/arm: smmuv3: Move definitions to a header >> Robin Murphy (1): >> xen/arm: smmuv3: Remove the page 1 fixup >> Zenghui Yu (2): >> xen/arm: smmuv3: Fix l1 stream table size in the error message >> xen/arm: smmuv3: Remove the unused fields for PREFETCH_CONFIG command >> Zhen Lei (1): >> xen/arm: smmuv3: Remove unnecessary oom message >> Zhou Wang (1): >> xen/arm: smmuv3: Ensure queue is read after updating prod pointer > > I didn't get the full series in my inbox. So I used the branch Bertrand pushed on gitlab [1]. That said, I had to tweak all the commit messages to remove the tags Issue-Id and Change-Id. > > I have also added Bertrand's reviewed-by tag on patch #3. > > It is now fully committed. Thanks for committing the series. Regards, Rahul
Hi Julien > On 6 Sep 2022, at 17:49, Julien Grall <julien@xen.org> wrote: > > Hi, > > On 06/09/2022 10:55, Rahul Singh wrote: >> This patch series merge the applicable Linux fixes to Xen. >> Bixuan Cui (1): >> xen/arm: smmuv3: Change *array into *const array >> Christophe JAILLET (1): >> xen/arm: smmuv3: Avoid open coded arithmetic in memory allocation >> Gustavo A. R. Silva (1): >> xen/arm: smmuv3: Fix fall-through warning for Clang >> Jean-Philippe Brucker (2): >> xen/arm: smmuv3: Fix endianness annotations >> xen/arm: smmuv3: Move definitions to a header >> Robin Murphy (1): >> xen/arm: smmuv3: Remove the page 1 fixup >> Zenghui Yu (2): >> xen/arm: smmuv3: Fix l1 stream table size in the error message >> xen/arm: smmuv3: Remove the unused fields for PREFETCH_CONFIG command >> Zhen Lei (1): >> xen/arm: smmuv3: Remove unnecessary oom message >> Zhou Wang (1): >> xen/arm: smmuv3: Ensure queue is read after updating prod pointer > > I didn't get the full series in my inbox. So I used the branch Bertrand pushed on gitlab [1]. That said, I had to tweak all the commit messages to remove the tags Issue-Id and Change-Id. Very sorry for that (should never do things in background during meetings). > > I have also added Bertrand's reviewed-by tag on patch #3. > > It is now fully committed. Thanks a lot Cheers Bertrand > > Cheers, > > [1] https://gitlab.com/xen-project/people/bmarquis/xen-arm-poc/-/tree/temp/smmuv3-fixes > >> xen/drivers/passthrough/arm/smmu-v3.c | 741 ++------------------------ >> xen/drivers/passthrough/arm/smmu-v3.h | 672 +++++++++++++++++++++++ >> 2 files changed, 708 insertions(+), 705 deletions(-) >> create mode 100644 xen/drivers/passthrough/arm/smmu-v3.h > > -- > Julien Grall