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* [BUG]: backfill min batch size test case failure on s390x
@ 2025-04-22 12:31 Pranav P
  2025-04-22 12:35 ` Pranav P
  2025-04-22 13:53 ` Patrick Steinhardt
  0 siblings, 2 replies; 3+ messages in thread
From: Pranav P @ 2025-04-22 12:31 UTC (permalink / raw)
  To: git@vger.kernel.org

Hi,                                                                                                                                                                                            
                                                                                                                                                                                               
When running `make test` on an s390x machine in Debian it is failing on 'do partial clone 2, backfill min batch size'                                                                          
Reference: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1102106                                                                                                                           
                                                                                                                                                                                               
After processing the command line arguments structure member min_batch_size should have had the value 20                                                                                       
                                                                                                                                                                                               
Instead of having the value 20 (--min-batch-size=20) it was having a very large value                                                                                                          
                                                                                                                                                                                               
min_batch_size in `struct backfill_context` is of type `size_t` and since in the function cmd_backfill, in the                                                                                 
options struct it is passed on to OPT_INTEGER, which eventually causes                                                                                                                         
                                                                                                                                                                                               
```                                                                                                                                                                                            
*(int *)opt->value = strtol(arg, (char **)&s, 10);                                                                                                                                             
```                                                                                                                                                                                            
in parse-options.c line 188. This is writing the data in the first 4 bytes of min_batch_size and on big endian                                                                                 
systems this will lead min_batch_size to be a big number. This issue is immediately visible in little endian systems.                                                                          
                                                                                                                                                                                               
Changing OPT_INTEGER to OPT_MAGNITUDE seems to be working on x86 and s390x                                                                                                                     
                                                                                                                                                                                               
```                                                                                                                                                                                            
diff --git a/builtin/backfill.c b/builtin/backfill.c                                                                                                                                           
index 18f9701487..33e1ea2f84 100644                                                                                                                                                            
--- a/builtin/backfill.c                                                                                                                                                                       
+++ b/builtin/backfill.c                                                                                                                                                                       
@@ -123,7 +123,7 @@ int cmd_backfill(int argc, const char **argv, const char *prefix, struct reposit                                                                                           
                .sparse = 0,                                                                                                                                                                   
        };                                                                                                                                                                                     
        struct option options[] = {                                                                                                                                                            
-               OPT_MAGNITUDE(0, "min-batch-size", &ctx.min_batch_size,                                                                                                                        
+               OPT_INTEGER(0, "min-batch-size", &ctx.min_batch_size,                                                                                                                          
                            N_("Minimum number of objects to request at a time")),                                                                                                             
                OPT_BOOL(0, "sparse", &ctx.sparse,                                                                                                                                             
                         N_("Restrict the missing objects to the current sparse-checkout")),                                                                                                   
```                                                                                                                                                                                            
                                                                                                                                                                                               
But on systems where size_t which not be unsigned long, this might lead to an issue.                                                                                                           
So, one other suggestion I have is to change the data type of min_batch_size from size_t to int. But I am not able to                                                                          
determine whether a practical upper bound for min_batch_size would exceed what an int variable can store.                                                                                      
With that clarification, I can a raise patch for the issue.                                                                                                                                    
                                                                                                                                                                                               
Please review the rest of the bug report below.

[System Info]                                                                                                                                                                                  
git version:                                                                                                                                                                                   
git version 2.49.0.391.g4bbb303af6                                                                                                                                                             
cpu: s390x                                                                                                                                                                                     
built from commit: 4bbb303af69990ccd05fe3a2eb58a1ce036f8220                                                                                                                                    
sizeof-long: 8                                                                                                                                                                                 
sizeof-size_t: 8                                                                                                                                                                               
shell-path: /bin/sh                                                                                                                                                                            
libcurl: 8.13.0                                                                                                                                                                                
OpenSSL: OpenSSL 3.4.1 11 Feb 2025                                                                                                                                                             
zlib: 1.3.1                                                                                                                                                                                    
SHA-1: SHA1_DC                                                                                                                                                                                 
SHA-256: SHA256_BLK                                                                                                                                                                            
uname: Linux 6.1.0-31-s390x #1 SMP Debian 6.1.128-1 (2025-02-07) s390x                                                                                                                         
compiler info: gnuc: 14.2                                                                                                                                                                      
libc info: glibc: 2.41                                                                                                                                                                         
$SHELL (typically, interactive shell): /bin/bash                                                                                                                                               
                                                                                                                                                                                               
                                                                                                                                                                                               
[Enabled Hooks]

I am fairly new to opensource and was following the `git bugreport`. So I am extremely sorry for any lack of clarity in the report.

Thanks,
Pranav

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [BUG]: backfill min batch size test case failure on s390x
  2025-04-22 12:31 [BUG]: backfill min batch size test case failure on s390x Pranav P
@ 2025-04-22 12:35 ` Pranav P
  2025-04-22 13:53 ` Patrick Steinhardt
  1 sibling, 0 replies; 3+ messages in thread
From: Pranav P @ 2025-04-22 12:35 UTC (permalink / raw)
  To: git@vger.kernel.org

Hi,

Sorry I had pasted the wrong git diff.
The corrected one is mentioned below.

diff --git a/builtin/backfill.c b/builtin/backfill.c
index 33e1ea2f84..18f9701487 100644
--- a/builtin/backfill.c
+++ b/builtin/backfill.c
@@ -123,7 +123,7 @@ int cmd_backfill(int argc, const char **argv, const char *prefix, struct reposit
                .sparse = 0,
        };
        struct option options[] = {
-               OPT_INTEGER(0, "min-batch-size", &ctx.min_batch_size,
+               OPT_MAGNITUDE(0, "min-batch-size", &ctx.min_batch_size,
                            N_("Minimum number of objects to request at a time")),
                OPT_BOOL(0, "sparse", &ctx.sparse,
                         N_("Restrict the missing objects to the current sparse-checkout")),
--

Thanks,
Pranav

________________________________________
From: Pranav P
Sent: Tuesday, April 22, 2025 6:01 PM
To: git@vger.kernel.org
Subject: [BUG]: backfill min batch size test case failure on s390x

Hi,

When running `make test` on an s390x machine in Debian it is failing on 'do partial clone 2, backfill min batch size'
Reference: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1102106

After processing the command line arguments structure member min_batch_size should have had the value 20

Instead of having the value 20 (--min-batch-size=20) it was having a very large value

min_batch_size in `struct backfill_context` is of type `size_t` and since in the function cmd_backfill, in the
options struct it is passed on to OPT_INTEGER, which eventually causes

```
*(int *)opt->value = strtol(arg, (char **)&s, 10);
```
in parse-options.c line 188. This is writing the data in the first 4 bytes of min_batch_size and on big endian
systems this will lead min_batch_size to be a big number. This issue is immediately visible in little endian systems.

Changing OPT_INTEGER to OPT_MAGNITUDE seems to be working on x86 and s390x

```
diff --git a/builtin/backfill.c b/builtin/backfill.c
index 18f9701487..33e1ea2f84 100644
--- a/builtin/backfill.c
+++ b/builtin/backfill.c
@@ -123,7 +123,7 @@ int cmd_backfill(int argc, const char **argv, const char *prefix, struct reposit
                .sparse = 0,
        };
        struct option options[] = {
-               OPT_MAGNITUDE(0, "min-batch-size", &ctx.min_batch_size,
+               OPT_INTEGER(0, "min-batch-size", &ctx.min_batch_size,
                            N_("Minimum number of objects to request at a time")),
                OPT_BOOL(0, "sparse", &ctx.sparse,
                         N_("Restrict the missing objects to the current sparse-checkout")),
```

But on systems where size_t which not be unsigned long, this might lead to an issue.
So, one other suggestion I have is to change the data type of min_batch_size from size_t to int. But I am not able to
determine whether a practical upper bound for min_batch_size would exceed what an int variable can store.
With that clarification, I can a raise patch for the issue.

Please review the rest of the bug report below.

[System Info]
git version:
git version 2.49.0.391.g4bbb303af6
cpu: s390x
built from commit: 4bbb303af69990ccd05fe3a2eb58a1ce036f8220
sizeof-long: 8
sizeof-size_t: 8
shell-path: /bin/sh
libcurl: 8.13.0
OpenSSL: OpenSSL 3.4.1 11 Feb 2025
zlib: 1.3.1
SHA-1: SHA1_DC
SHA-256: SHA256_BLK
uname: Linux 6.1.0-31-s390x #1 SMP Debian 6.1.128-1 (2025-02-07) s390x
compiler info: gnuc: 14.2
libc info: glibc: 2.41
$SHELL (typically, interactive shell): /bin/bash


[Enabled Hooks]

I am fairly new to opensource and was following the `git bugreport`. So I am extremely sorry for any lack of clarity in the report.

Thanks,
Pranav

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [BUG]: backfill min batch size test case failure on s390x
  2025-04-22 12:31 [BUG]: backfill min batch size test case failure on s390x Pranav P
  2025-04-22 12:35 ` Pranav P
@ 2025-04-22 13:53 ` Patrick Steinhardt
  1 sibling, 0 replies; 3+ messages in thread
From: Patrick Steinhardt @ 2025-04-22 13:53 UTC (permalink / raw)
  To: Pranav P; +Cc: git@vger.kernel.org

Hi,

On Tue, Apr 22, 2025 at 12:31:18PM +0000, Pranav P wrote:
> Hi,
>
> When running `make test` on an s390x machine in Debian it is failing on 'do partial clone 2, backfill min batch size'
> Reference: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1102106
>
> After processing the command line arguments structure member min_batch_size should have had the value 20
>
> Instead of having the value 20 (--min-batch-size=20) it was having a very large value
>
> min_batch_size in `struct backfill_context` is of type `size_t` and since in the function cmd_backfill, in the
> options struct it is passed on to OPT_INTEGER, which eventually causes
>
> ```
> *(int *)opt->value = strtol(arg, (char **)&s, 10);
> ```
> in parse-options.c line 188. This is writing the data in the first 4 bytes of min_batch_size and on big endian
> systems this will lead min_batch_size to be a big number. This issue is immediately visible in little endian systems.
>
> Changing OPT_INTEGER to OPT_MAGNITUDE seems to be working on x86 and s390x

Yup, indeed.

> ```
> diff --git a/builtin/backfill.c b/builtin/backfill.c
> index 18f9701487..33e1ea2f84 100644
> --- a/builtin/backfill.c
> +++ b/builtin/backfill.c
> @@ -123,7 +123,7 @@ int cmd_backfill(int argc, const char **argv, const char *prefix, struct reposit
>                 .sparse = 0,
>         };
>         struct option options[] = {
> -               OPT_MAGNITUDE(0, "min-batch-size", &ctx.min_batch_size,
> +               OPT_INTEGER(0, "min-batch-size", &ctx.min_batch_size,
>                             N_("Minimum number of objects to request at a time")),
>                 OPT_BOOL(0, "sparse", &ctx.sparse,
>                          N_("Restrict the missing objects to the current sparse-checkout")),
> ```
>
> But on systems where size_t which not be unsigned long, this might lead to an issue.
> So, one other suggestion I have is to change the data type of min_batch_size from size_t to int. But I am not able to
> determine whether a practical upper bound for min_batch_size would exceed what an int variable can store.
> With that clarification, I can a raise patch for the issue.

True, as well. Overall the current state is a bit unfortunate because
it's so easy to get this wrong, and the compiler won't even spit out a
warning.

> I am fairly new to opensource and was following the `git bugreport`. So I am extremely sorry for any lack of clarity in the report.

No need to be sorry, this bug report contains all the details we'd need
and is of quite high quality :) The only thing is that we've already got
this bug reported via [1].

The underlying issue is addressed via [2], which has already been merged
to `next`. It also fixes the underlying issue you observed with
different integer widths as well as with signedness.

Thanks!

Patrick

[1]: https://lore.kernel.org/git/89257ab82cd60d135cce02d51eacee7ec35c1c37.camel@physik.fu-berlin.de/
[2]: https://lore.kernel.org/git/20250401-b4-pks-parse-options-integers-v1-0-a628ad40c3b4@pks.im/

^ permalink raw reply	[flat|nested] 3+ messages in thread

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2025-04-22 12:31 [BUG]: backfill min batch size test case failure on s390x Pranav P
2025-04-22 12:35 ` Pranav P
2025-04-22 13:53 ` Patrick Steinhardt

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