diff mbox series

[v4,1/2] dmaengine: tegra210-adma: Fix build error due to 64-by-32 division

Message ID 20250205033131.3920801-2-mkumard@nvidia.com (mailing list archive)
State Superseded
Commit 17987453a9d997c4d0749abc52f047bfa275427a
Headers show
Series Tegra ADMA fixes | expand

Commit Message

Mohan Kumar D Feb. 5, 2025, 3:31 a.m. UTC
Kernel test robot reported the build errors on 32-bit platforms due to
plain 64-by-32 division. Following build erros were reported.

   "ERROR: modpost: "__udivdi3" [drivers/dma/tegra210-adma.ko] undefined!
    ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe':
    tegra210-adma.c:(.text+0x12cf): undefined reference to `__udivdi3'"

This can be fixed by using div_u64() for the adma address space

Fixes: 68811c928f88 ("dmaengine: tegra210-adma: Support channel page")
Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202412250204.GCQhdKe3-lkp@intel.com/
Signed-off-by: Mohan Kumar D <mkumard@nvidia.com>
---
 drivers/dma/tegra210-adma.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

Comments

Jon Hunter Feb. 5, 2025, 11:27 a.m. UTC | #1
On 05/02/2025 03:31, Mohan Kumar D wrote:
> Kernel test robot reported the build errors on 32-bit platforms due to
> plain 64-by-32 division. Following build erros were reported.
> 
>     "ERROR: modpost: "__udivdi3" [drivers/dma/tegra210-adma.ko] undefined!
>      ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe':
>      tegra210-adma.c:(.text+0x12cf): undefined reference to `__udivdi3'"
> 
> This can be fixed by using div_u64() for the adma address space
> 
> Fixes: 68811c928f88 ("dmaengine: tegra210-adma: Support channel page")
> Cc: stable@vger.kernel.org
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202412250204.GCQhdKe3-lkp@intel.com/
> Signed-off-by: Mohan Kumar D <mkumard@nvidia.com>
> ---
>   drivers/dma/tegra210-adma.c | 15 +++++++++++----
>   1 file changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c
> index 6896da8ac7ef..a0bd4822ed80 100644
> --- a/drivers/dma/tegra210-adma.c
> +++ b/drivers/dma/tegra210-adma.c
> @@ -887,7 +887,8 @@ static int tegra_adma_probe(struct platform_device *pdev)
>   	const struct tegra_adma_chip_data *cdata;
>   	struct tegra_adma *tdma;
>   	struct resource *res_page, *res_base;
> -	int ret, i, page_no;
> +	u64 page_no, page_offset;
> +	int ret, i;
>   
>   	cdata = of_device_get_match_data(&pdev->dev);
>   	if (!cdata) {
> @@ -914,10 +915,16 @@ static int tegra_adma_probe(struct platform_device *pdev)
>   
>   		res_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "global");
>   		if (res_base) {
> -			page_no = (res_page->start - res_base->start) / cdata->ch_base_offset;
> -			if (page_no <= 0)
> +			if (WARN_ON(res_page->start <= res_base->start))
>   				return -EINVAL;
> -			tdma->ch_page_no = page_no - 1;
> +
> +			page_offset = res_page->start - res_base->start;
> +			page_no = div_u64(page_offset, cdata->ch_base_offset);
> +
> +			if (WARN_ON(page_no == 0))
> +				return -EINVAL;

Sorry to be pedantic but should this now be ...

if (WARN_ON((page_no == 0) || (page_no > UINT_MAX)))

Jon

> +
> +			tdma->ch_page_no = lower_32_bits(page_no) - 1;
>   			tdma->base_addr = devm_ioremap_resource(&pdev->dev, res_base);
>   			if (IS_ERR(tdma->base_addr))
>   				return PTR_ERR(tdma->base_addr);
Jon Hunter Feb. 5, 2025, 11:28 a.m. UTC | #2
On 05/02/2025 11:27, Jon Hunter wrote:
> 
> 
> On 05/02/2025 03:31, Mohan Kumar D wrote:
>> Kernel test robot reported the build errors on 32-bit platforms due to
>> plain 64-by-32 division. Following build erros were reported.
>>
>>     "ERROR: modpost: "__udivdi3" [drivers/dma/tegra210-adma.ko] 
>> undefined!
>>      ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe':
>>      tegra210-adma.c:(.text+0x12cf): undefined reference to `__udivdi3'"
>>
>> This can be fixed by using div_u64() for the adma address space
>>
>> Fixes: 68811c928f88 ("dmaengine: tegra210-adma: Support channel page")
>> Cc: stable@vger.kernel.org
>> Reported-by: kernel test robot <lkp@intel.com>
>> Closes: https://lore.kernel.org/oe-kbuild-all/202412250204.GCQhdKe3- 
>> lkp@intel.com/
>> Signed-off-by: Mohan Kumar D <mkumard@nvidia.com>
>> ---
>>   drivers/dma/tegra210-adma.c | 15 +++++++++++----
>>   1 file changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c
>> index 6896da8ac7ef..a0bd4822ed80 100644
>> --- a/drivers/dma/tegra210-adma.c
>> +++ b/drivers/dma/tegra210-adma.c
>> @@ -887,7 +887,8 @@ static int tegra_adma_probe(struct platform_device 
>> *pdev)
>>       const struct tegra_adma_chip_data *cdata;
>>       struct tegra_adma *tdma;
>>       struct resource *res_page, *res_base;
>> -    int ret, i, page_no;
>> +    u64 page_no, page_offset;
>> +    int ret, i;
>>       cdata = of_device_get_match_data(&pdev->dev);
>>       if (!cdata) {
>> @@ -914,10 +915,16 @@ static int tegra_adma_probe(struct 
>> platform_device *pdev)
>>           res_base = platform_get_resource_byname(pdev, 
>> IORESOURCE_MEM, "global");
>>           if (res_base) {
>> -            page_no = (res_page->start - res_base->start) / cdata- 
>> >ch_base_offset;
>> -            if (page_no <= 0)
>> +            if (WARN_ON(res_page->start <= res_base->start))
>>                   return -EINVAL;
>> -            tdma->ch_page_no = page_no - 1;
>> +
>> +            page_offset = res_page->start - res_base->start;
>> +            page_no = div_u64(page_offset, cdata->ch_base_offset);
>> +
>> +            if (WARN_ON(page_no == 0))
>> +                return -EINVAL;
> 
> Sorry to be pedantic but should this now be ...
> 
> if (WARN_ON((page_no == 0) || (page_no > UINT_MAX)))

Nevermind, patch 2/2 addresses this.

Jon
Thierry Reding Feb. 5, 2025, 1:25 p.m. UTC | #3
On Wed, Feb 05, 2025 at 09:01:30AM +0530, Mohan Kumar D wrote:
> Kernel test robot reported the build errors on 32-bit platforms due to
> plain 64-by-32 division. Following build erros were reported.
> 
>    "ERROR: modpost: "__udivdi3" [drivers/dma/tegra210-adma.ko] undefined!
>     ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe':
>     tegra210-adma.c:(.text+0x12cf): undefined reference to `__udivdi3'"
> 
> This can be fixed by using div_u64() for the adma address space
> 
> Fixes: 68811c928f88 ("dmaengine: tegra210-adma: Support channel page")
> Cc: stable@vger.kernel.org
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202412250204.GCQhdKe3-lkp@intel.com/
> Signed-off-by: Mohan Kumar D <mkumard@nvidia.com>
> ---
>  drivers/dma/tegra210-adma.c | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)

Acked-by: Thierry Reding <treding@nvidia.com>
Vinod Koul Feb. 10, 2025, 11:02 a.m. UTC | #4
Hi Mohan,

On 05-02-25, 09:01, Mohan Kumar D wrote:
> Kernel test robot reported the build errors on 32-bit platforms due to
> plain 64-by-32 division. Following build erros were reported.

Patch should describe the change! Please revise subject to describe that
and not fix build error... This can come in changelog and below para is
apt

> 
>    "ERROR: modpost: "__udivdi3" [drivers/dma/tegra210-adma.ko] undefined!
>     ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe':
>     tegra210-adma.c:(.text+0x12cf): undefined reference to `__udivdi3'"
> 
> This can be fixed by using div_u64() for the adma address space
> 
> Fixes: 68811c928f88 ("dmaengine: tegra210-adma: Support channel page")
> Cc: stable@vger.kernel.org
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202412250204.GCQhdKe3-lkp@intel.com/
> Signed-off-by: Mohan Kumar D <mkumard@nvidia.com>
> ---
>  drivers/dma/tegra210-adma.c | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c
> index 6896da8ac7ef..a0bd4822ed80 100644
> --- a/drivers/dma/tegra210-adma.c
> +++ b/drivers/dma/tegra210-adma.c
> @@ -887,7 +887,8 @@ static int tegra_adma_probe(struct platform_device *pdev)
>  	const struct tegra_adma_chip_data *cdata;
>  	struct tegra_adma *tdma;
>  	struct resource *res_page, *res_base;
> -	int ret, i, page_no;
> +	u64 page_no, page_offset;
> +	int ret, i;
>  
>  	cdata = of_device_get_match_data(&pdev->dev);
>  	if (!cdata) {
> @@ -914,10 +915,16 @@ static int tegra_adma_probe(struct platform_device *pdev)
>  
>  		res_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "global");
>  		if (res_base) {
> -			page_no = (res_page->start - res_base->start) / cdata->ch_base_offset;
> -			if (page_no <= 0)
> +			if (WARN_ON(res_page->start <= res_base->start))
>  				return -EINVAL;
> -			tdma->ch_page_no = page_no - 1;
> +
> +			page_offset = res_page->start - res_base->start;
> +			page_no = div_u64(page_offset, cdata->ch_base_offset);
> +
> +			if (WARN_ON(page_no == 0))
> +				return -EINVAL;
> +
> +			tdma->ch_page_no = lower_32_bits(page_no) - 1;
>  			tdma->base_addr = devm_ioremap_resource(&pdev->dev, res_base);
>  			if (IS_ERR(tdma->base_addr))
>  				return PTR_ERR(tdma->base_addr);
> -- 
> 2.25.1
Mohan Kumar D Feb. 10, 2025, 11:15 a.m. UTC | #5
On 10-02-2025 16:32, Vinod Koul wrote:
> External email: Use caution opening links or attachments
>
>
> Hi Mohan,
>
> On 05-02-25, 09:01, Mohan Kumar D wrote:
>> Kernel test robot reported the build errors on 32-bit platforms due to
>> plain 64-by-32 division. Following build erros were reported.
> Patch should describe the change! Please revise subject to describe that
> and not fix build error... This can come in changelog and below para is
> apt
Sure, Will update the subject and resend the updated patch
>>     "ERROR: modpost: "__udivdi3" [drivers/dma/tegra210-adma.ko] undefined!
>>      ld: drivers/dma/tegra210-adma.o: in function `tegra_adma_probe':
>>      tegra210-adma.c:(.text+0x12cf): undefined reference to `__udivdi3'"
>>
>> This can be fixed by using div_u64() for the adma address space
>>
>> Fixes: 68811c928f88 ("dmaengine: tegra210-adma: Support channel page")
>> Cc: stable@vger.kernel.org
>> Reported-by: kernel test robot <lkp@intel.com>
>> Closes: https://lore.kernel.org/oe-kbuild-all/202412250204.GCQhdKe3-lkp@intel.com/
>> Signed-off-by: Mohan Kumar D <mkumard@nvidia.com>
>> ---
>>   drivers/dma/tegra210-adma.c | 15 +++++++++++----
>>   1 file changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c
>> index 6896da8ac7ef..a0bd4822ed80 100644
>> --- a/drivers/dma/tegra210-adma.c
>> +++ b/drivers/dma/tegra210-adma.c
>> @@ -887,7 +887,8 @@ static int tegra_adma_probe(struct platform_device *pdev)
>>        const struct tegra_adma_chip_data *cdata;
>>        struct tegra_adma *tdma;
>>        struct resource *res_page, *res_base;
>> -     int ret, i, page_no;
>> +     u64 page_no, page_offset;
>> +     int ret, i;
>>
>>        cdata = of_device_get_match_data(&pdev->dev);
>>        if (!cdata) {
>> @@ -914,10 +915,16 @@ static int tegra_adma_probe(struct platform_device *pdev)
>>
>>                res_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "global");
>>                if (res_base) {
>> -                     page_no = (res_page->start - res_base->start) / cdata->ch_base_offset;
>> -                     if (page_no <= 0)
>> +                     if (WARN_ON(res_page->start <= res_base->start))
>>                                return -EINVAL;
>> -                     tdma->ch_page_no = page_no - 1;
>> +
>> +                     page_offset = res_page->start - res_base->start;
>> +                     page_no = div_u64(page_offset, cdata->ch_base_offset);
>> +
>> +                     if (WARN_ON(page_no == 0))
>> +                             return -EINVAL;
>> +
>> +                     tdma->ch_page_no = lower_32_bits(page_no) - 1;
>>                        tdma->base_addr = devm_ioremap_resource(&pdev->dev, res_base);
>>                        if (IS_ERR(tdma->base_addr))
>>                                return PTR_ERR(tdma->base_addr);
>> --
>> 2.25.1
> --
> ~Vinod
Vinod Koul Feb. 10, 2025, 11:23 a.m. UTC | #6
On 10-02-25, 16:45, Mohan Kumar D wrote:
> 
> On 10-02-2025 16:32, Vinod Koul wrote:
> > External email: Use caution opening links or attachments
> > 
> > 
> > Hi Mohan,
> > 
> > On 05-02-25, 09:01, Mohan Kumar D wrote:
> > > Kernel test robot reported the build errors on 32-bit platforms due to
> > > plain 64-by-32 division. Following build erros were reported.
> > Patch should describe the change! Please revise subject to describe that
> > and not fix build error... This can come in changelog and below para is
> > apt
> Sure, Will update the subject and resend the updated patch

Please collect the acks as well
diff mbox series

Patch

diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c
index 6896da8ac7ef..a0bd4822ed80 100644
--- a/drivers/dma/tegra210-adma.c
+++ b/drivers/dma/tegra210-adma.c
@@ -887,7 +887,8 @@  static int tegra_adma_probe(struct platform_device *pdev)
 	const struct tegra_adma_chip_data *cdata;
 	struct tegra_adma *tdma;
 	struct resource *res_page, *res_base;
-	int ret, i, page_no;
+	u64 page_no, page_offset;
+	int ret, i;
 
 	cdata = of_device_get_match_data(&pdev->dev);
 	if (!cdata) {
@@ -914,10 +915,16 @@  static int tegra_adma_probe(struct platform_device *pdev)
 
 		res_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "global");
 		if (res_base) {
-			page_no = (res_page->start - res_base->start) / cdata->ch_base_offset;
-			if (page_no <= 0)
+			if (WARN_ON(res_page->start <= res_base->start))
 				return -EINVAL;
-			tdma->ch_page_no = page_no - 1;
+
+			page_offset = res_page->start - res_base->start;
+			page_no = div_u64(page_offset, cdata->ch_base_offset);
+
+			if (WARN_ON(page_no == 0))
+				return -EINVAL;
+
+			tdma->ch_page_no = lower_32_bits(page_no) - 1;
 			tdma->base_addr = devm_ioremap_resource(&pdev->dev, res_base);
 			if (IS_ERR(tdma->base_addr))
 				return PTR_ERR(tdma->base_addr);