Re: [PATCH v2] drivers/virt/fsl_hypervisor: Correcting error handling path
On Thu, Jul 30, 2020 at 6:30 AM John Hubbard wrote: > > On 7/29/20 12:01 PM, Souptick Joarder wrote: > > First, when memory allocation for sg_list_unaligned failed, there > > is no point of calling put_pages() as we haven't pinned any pages. > > > > Second, if get_user_pages_fast() failed we should unpinned num_pinned > > pages, no point of checking till num_pages. > > Hi Souptick, > > For both of the above, the wording "no point" is so overly gentle as > to be misleading. That's because calling put_page() on any pages beyond > num_pinned is a *bug*. > > So let's reword that. And let's change the patch subject from "Correcting" to > "fix". > > And probably good to add a Fixes: tag, too. Is there any scripts/ settings to fetch Fixes: tag other than using git blame ? > > More: > > > > > This will address both. > > > > Signed-off-by: Souptick Joarder > > Reviewed-by: Dan Carpenter > > Cc: John Hubbard > > --- > > v2: > > Added review tag. > > > > drivers/virt/fsl_hypervisor.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c > > index 1b0b11b..ea344d7 100644 > > --- a/drivers/virt/fsl_hypervisor.c > > +++ b/drivers/virt/fsl_hypervisor.c > > @@ -157,7 +157,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy > > __user *p) > > > > unsigned int i; > > long ret = 0; > > - int num_pinned; /* return value from get_user_pages() */ > > + int num_pinned = 0; /* return value from get_user_pages() */ > > phys_addr_t remote_paddr; /* The next address in the remote buffer */ > > uint32_t count; /* The number of bytes left to copy */ > > > > @@ -293,7 +293,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy > > __user *p) > > > > exit: > > if (pages) { > > - for (i = 0; i < num_pages; i++) > > + for (i = 0; i < num_pinned; i++) > > if (pages[i]) > > I suspect that this "if" is unnecessary now. > > Either way, the diff itself looks good to me, so with the wording changes to > the commit description, you can add: > > Reviewed-by: John Hubbard > > thanks, > -- > John Hubbard > NVIDIA > > > put_page(pages[i]); > > } > > >
Re: [PATCH v2] drivers/virt/fsl_hypervisor: Correcting error handling path
On 7/29/20 12:01 PM, Souptick Joarder wrote: First, when memory allocation for sg_list_unaligned failed, there is no point of calling put_pages() as we haven't pinned any pages. Second, if get_user_pages_fast() failed we should unpinned num_pinned pages, no point of checking till num_pages. Hi Souptick, For both of the above, the wording "no point" is so overly gentle as to be misleading. That's because calling put_page() on any pages beyond num_pinned is a *bug*. So let's reword that. And let's change the patch subject from "Correcting" to "fix". And probably good to add a Fixes: tag, too. More: This will address both. Signed-off-by: Souptick Joarder Reviewed-by: Dan Carpenter Cc: John Hubbard --- v2: Added review tag. drivers/virt/fsl_hypervisor.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c index 1b0b11b..ea344d7 100644 --- a/drivers/virt/fsl_hypervisor.c +++ b/drivers/virt/fsl_hypervisor.c @@ -157,7 +157,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p) unsigned int i; long ret = 0; - int num_pinned; /* return value from get_user_pages() */ + int num_pinned = 0; /* return value from get_user_pages() */ phys_addr_t remote_paddr; /* The next address in the remote buffer */ uint32_t count; /* The number of bytes left to copy */ @@ -293,7 +293,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p) exit: if (pages) { - for (i = 0; i < num_pages; i++) + for (i = 0; i < num_pinned; i++) if (pages[i]) I suspect that this "if" is unnecessary now. Either way, the diff itself looks good to me, so with the wording changes to the commit description, you can add: Reviewed-by: John Hubbard thanks, -- John Hubbard NVIDIA put_page(pages[i]); }
[PATCH v2] drivers/virt/fsl_hypervisor: Correcting error handling path
First, when memory allocation for sg_list_unaligned failed, there is no point of calling put_pages() as we haven't pinned any pages. Second, if get_user_pages_fast() failed we should unpinned num_pinned pages, no point of checking till num_pages. This will address both. Signed-off-by: Souptick Joarder Reviewed-by: Dan Carpenter Cc: John Hubbard --- v2: Added review tag. drivers/virt/fsl_hypervisor.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c index 1b0b11b..ea344d7 100644 --- a/drivers/virt/fsl_hypervisor.c +++ b/drivers/virt/fsl_hypervisor.c @@ -157,7 +157,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p) unsigned int i; long ret = 0; - int num_pinned; /* return value from get_user_pages() */ + int num_pinned = 0; /* return value from get_user_pages() */ phys_addr_t remote_paddr; /* The next address in the remote buffer */ uint32_t count; /* The number of bytes left to copy */ @@ -293,7 +293,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p) exit: if (pages) { - for (i = 0; i < num_pages; i++) + for (i = 0; i < num_pinned; i++) if (pages[i]) put_page(pages[i]); } -- 1.9.1
Re: [PATCH v2] drivers/virt/fsl_hypervisor: Correcting error handling path
On Mon, Jun 22, 2020 at 10:05 PM Souptick Joarder wrote: > > On Wed, Jun 17, 2020 at 8:22 AM Souptick Joarder wrote: > > > > First, when memory allocation for sg_list_unaligned failed, there > > is no point of calling put_pages() as we haven't pinned any pages. > > > > Second, if get_user_pages_fast() failed we should unpinned num_pinned > > pages, no point of checking till num_pages. > > > > This will address both. > > > > Signed-off-by: Souptick Joarder > > Reviewed-by: Dan Carpenter > > Cc: John Hubbard > > Any suggestion, what is the right tree to take this patch forward ? If no further comment, can we get this patch in queue for 5.9 ? > > > --- > > v2: > > Added review tag. > > > > drivers/virt/fsl_hypervisor.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c > > index 1b0b11b..ea344d7 100644 > > --- a/drivers/virt/fsl_hypervisor.c > > +++ b/drivers/virt/fsl_hypervisor.c > > @@ -157,7 +157,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy > > __user *p) > > > > unsigned int i; > > long ret = 0; > > - int num_pinned; /* return value from get_user_pages() */ > > + int num_pinned = 0; /* return value from get_user_pages() */ > > phys_addr_t remote_paddr; /* The next address in the remote buffer > > */ > > uint32_t count; /* The number of bytes left to copy */ > > > > @@ -293,7 +293,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy > > __user *p) > > > > exit: > > if (pages) { > > - for (i = 0; i < num_pages; i++) > > + for (i = 0; i < num_pinned; i++) > > if (pages[i]) > > put_page(pages[i]); > > } > > -- > > 1.9.1 > >
Re: [PATCH v2] drivers/virt/fsl_hypervisor: Correcting error handling path
On Wed, Jun 17, 2020 at 8:22 AM Souptick Joarder wrote: > > First, when memory allocation for sg_list_unaligned failed, there > is no point of calling put_pages() as we haven't pinned any pages. > > Second, if get_user_pages_fast() failed we should unpinned num_pinned > pages, no point of checking till num_pages. > > This will address both. > > Signed-off-by: Souptick Joarder > Reviewed-by: Dan Carpenter > Cc: John Hubbard Any suggestion, what is the right tree to take this patch forward ? > --- > v2: > Added review tag. > > drivers/virt/fsl_hypervisor.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c > index 1b0b11b..ea344d7 100644 > --- a/drivers/virt/fsl_hypervisor.c > +++ b/drivers/virt/fsl_hypervisor.c > @@ -157,7 +157,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy > __user *p) > > unsigned int i; > long ret = 0; > - int num_pinned; /* return value from get_user_pages() */ > + int num_pinned = 0; /* return value from get_user_pages() */ > phys_addr_t remote_paddr; /* The next address in the remote buffer */ > uint32_t count; /* The number of bytes left to copy */ > > @@ -293,7 +293,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy > __user *p) > > exit: > if (pages) { > - for (i = 0; i < num_pages; i++) > + for (i = 0; i < num_pinned; i++) > if (pages[i]) > put_page(pages[i]); > } > -- > 1.9.1 >
[PATCH v2] drivers/virt/fsl_hypervisor: Correcting error handling path
First, when memory allocation for sg_list_unaligned failed, there is no point of calling put_pages() as we haven't pinned any pages. Second, if get_user_pages_fast() failed we should unpinned num_pinned pages, no point of checking till num_pages. This will address both. Signed-off-by: Souptick Joarder Reviewed-by: Dan Carpenter Cc: John Hubbard --- v2: Added review tag. drivers/virt/fsl_hypervisor.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c index 1b0b11b..ea344d7 100644 --- a/drivers/virt/fsl_hypervisor.c +++ b/drivers/virt/fsl_hypervisor.c @@ -157,7 +157,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p) unsigned int i; long ret = 0; - int num_pinned; /* return value from get_user_pages() */ + int num_pinned = 0; /* return value from get_user_pages() */ phys_addr_t remote_paddr; /* The next address in the remote buffer */ uint32_t count; /* The number of bytes left to copy */ @@ -293,7 +293,7 @@ static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p) exit: if (pages) { - for (i = 0; i < num_pages; i++) + for (i = 0; i < num_pinned; i++) if (pages[i]) put_page(pages[i]); } -- 1.9.1