[PATCH 2/2] log: Suggest using -d guest_error,memaccess instead of guest_errors

BALATON Zoltan posted 2 patches 1 month, 2 weeks ago
There is a newer version of this series
[PATCH 2/2] log: Suggest using -d guest_error,memaccess instead of guest_errors
Posted by BALATON Zoltan 1 month, 2 weeks ago
Rename guest_errors to guest_error to match the log constant and print
a warning for -d guest_errors to remind using guest_error,memaccess
instead but preserve previous behaviour for convenience.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
---
As this is a debug switch I think no formal deprecation is needed but
this is to allow people to change their commands and scripts then it
may be removed eventually.

 docs/devel/secure-coding-practices.rst | 2 +-
 tests/avocado/smmu.py                  | 2 +-
 tests/qtest/pnv-host-i2c-test.c        | 2 +-
 util/log.c                             | 6 +++++-
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/docs/devel/secure-coding-practices.rst b/docs/devel/secure-coding-practices.rst
index 0454cc527e..b330b01956 100644
--- a/docs/devel/secure-coding-practices.rst
+++ b/docs/devel/secure-coding-practices.rst
@@ -85,7 +85,7 @@ request completes.  Unexpected accesses must not cause memory corruption or
 leaks in QEMU.
 
 Invalid device register accesses can be reported with
-``qemu_log_mask(LOG_GUEST_ERROR, ...)``.  The ``-d guest_errors`` command-line
+``qemu_log_mask(LOG_GUEST_ERROR, ...)``.  The ``-d guest_error`` command-line
 option enables these log messages.
 
 Live Migration
diff --git a/tests/avocado/smmu.py b/tests/avocado/smmu.py
index 83fd79e922..7ed836c12d 100644
--- a/tests/avocado/smmu.py
+++ b/tests/avocado/smmu.py
@@ -46,7 +46,7 @@ def common_vm_setup(self, custom_kernel=False):
         self.vm.add_args("-accel", "kvm")
         self.vm.add_args("-cpu", "host")
         self.vm.add_args("-machine", "iommu=smmuv3")
-        self.vm.add_args("-d", "guest_errors")
+        self.vm.add_args("-d", "guest_error,memaccess")
         self.vm.add_args('-bios', os.path.join(BUILD_DIR, 'pc-bios',
                          'edk2-aarch64-code.fd'))
         self.vm.add_args('-device', 'virtio-rng-pci,rng=rng0')
diff --git a/tests/qtest/pnv-host-i2c-test.c b/tests/qtest/pnv-host-i2c-test.c
index 7f64d597ac..63a2acf9de 100644
--- a/tests/qtest/pnv-host-i2c-test.c
+++ b/tests/qtest/pnv-host-i2c-test.c
@@ -418,7 +418,7 @@ static void test_host_i2c(const void *data)
 
     qts = qtest_initf("-M %s -smp %d,cores=1,threads=%d -nographic "
                       "-nodefaults -serial mon:stdio -S "
-                      "-d guest_errors",
+                      "-d guest_error,memaccess",
                       machine, SMT, SMT);
 
     /* Check the I2C master status registers after POR */
diff --git a/util/log.c b/util/log.c
index 1aa7396277..279c2b5cfb 100644
--- a/util/log.c
+++ b/util/log.c
@@ -486,7 +486,7 @@ const QEMULogItem qemu_log_items[] = {
       "show CPU state before CPU resets" },
     { LOG_UNIMP, "unimp",
       "log unimplemented functionality" },
-    { LOG_GUEST_ERROR, "guest_errors",
+    { LOG_GUEST_ERROR, "guest_error",
       "log when the guest OS does something invalid (eg accessing a\n"
       "non-existent register)" },
     { CPU_LOG_PAGE, "page",
@@ -521,6 +521,10 @@ int qemu_str_to_log_mask(const char *str)
             for (item = qemu_log_items; item->mask != 0; item++) {
                 mask |= item->mask;
             }
+        } else if (g_str_equal(*tmp, "guest_errors")) {
+            warn_report("Log option guest_errors is deprecated. "
+                        "Use guest_error,memaccess instead.");
+            mask |= LOG_GUEST_ERROR | LOG_MEM_ACCESS;
 #ifdef CONFIG_TRACE_LOG
         } else if (g_str_has_prefix(*tmp, "trace:") && (*tmp)[6] != '\0') {
             trace_enable_events((*tmp) + 6);
-- 
2.30.9
Re: [PATCH 2/2] log: Suggest using -d guest_error,memaccess instead of guest_errors
Posted by Peter Maydell 1 month, 1 week ago
On Sun, 6 Oct 2024 at 17:49, BALATON Zoltan <balaton@eik.bme.hu> wrote:
>
> Rename guest_errors to guest_error to match the log constant

I don't think this is a good reason to change the user-facing
behaviour. Also, I don't think the existing names are so bad:

 -d guest_errors
   this is plural because we are asking to log all guest errors
 qemu_log_mask(LOG_GUEST_ERROR, ...)
   this is singular because we are logging a single error here.

If we do want to change things for consistency, we should decide
on what the user-facing option name ought to be (and I think
plural is fine), and then change the internal define to match
that, not vice versa.

> and print
> a warning for -d guest_errors to remind using guest_error,memaccess
> instead but preserve previous behaviour for convenience.
>
> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>

thanks
-- PMM
Re: [PATCH 2/2] log: Suggest using -d guest_error,memaccess instead of guest_errors
Posted by BALATON Zoltan 1 month, 1 week ago
On Mon, 14 Oct 2024, Peter Maydell wrote:
> On Sun, 6 Oct 2024 at 17:49, BALATON Zoltan <balaton@eik.bme.hu> wrote:
>>
>> Rename guest_errors to guest_error to match the log constant
>
> I don't think this is a good reason to change the user-facing
> behaviour. Also, I don't think the existing names are so bad:
>
> -d guest_errors
>   this is plural because we are asking to log all guest errors
> qemu_log_mask(LOG_GUEST_ERROR, ...)
>   this is singular because we are logging a single error here.
>
> If we do want to change things for consistency, we should decide
> on what the user-facing option name ought to be (and I think
> plural is fine), and then change the internal define to match
> that, not vice versa.

The point of this patch is not to match the define with the option. 
Originally I had a patch that just separated memory access logs and left 
guest_errors as it is but without the memory access logs. But I think 
Philippe said that he likes this option to log both. So to satisfy all 
needs I'v added this patch to preserve what guest_errors is doing now but 
let it be changed later after some time for people to get used to it (or 
leave it if that's what people like). Leaving guest_errors to log both is 
not an option as I want to have separate options for memory access and 
guest errors so they can be turned on or off independently. So if we have 
to keep guest_errors to log both then we need a new option for just guest 
errors for which one that matches the definen seemed like an easy way that 
is consistent with the other debug options. I'd be OK to leave 
guest_errors but without the memory access logs, then this patch is not 
needed but some people did not like that before.

Regards,
BALATON Zoltan

>> and print
>> a warning for -d guest_errors to remind using guest_error,memaccess
>> instead but preserve previous behaviour for convenience.
>>
>> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
>
> thanks
> -- PMM
>
>