Re: [PATCH v2 RESEND 1/2] arm, arm64: change_memory_common with numpages == 0 should be no-op.
Hi Will, On 26.01.2016 17:59, Will Deacon wrote: > Hi Mika, > > On Tue, Jan 26, 2016 at 04:59:52PM +0200, mika.pentt...@nextfour.com wrote: >> From: Mika Penttilä >> >> This makes the caller set_memory_xx() consistent with x86. >> >> arm64 part is rebased on 4.5.0-rc1 with Ard's patch >> >> lkml.kernel.org/g/<1453125665-26627-1-git-send-email-ard.biesheu...@linaro.org> >> applied. >> >> Signed-off-by: Mika Penttilä mika.pentt...@nextfour.com >> Reviewed-by: Laura Abbott >> Acked-by: David Rientjes >> >> --- >> arch/arm/mm/pageattr.c | 3 +++ >> arch/arm64/mm/pageattr.c | 3 +++ >> 2 files changed, 6 insertions(+) >> >> diff --git a/arch/arm/mm/pageattr.c b/arch/arm/mm/pageattr.c >> index cf30daf..d19b1ad 100644 >> --- a/arch/arm/mm/pageattr.c >> +++ b/arch/arm/mm/pageattr.c >> @@ -49,6 +49,9 @@ static int change_memory_common(unsigned long addr, int >> numpages, >> WARN_ON_ONCE(1); >> } >> >> +if (!numpages) >> +return 0; >> + >> if (start < MODULES_VADDR || start >= MODULES_END) >> return -EINVAL; >> >> diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c >> index 1360a02..b582fc2 100644 >> --- a/arch/arm64/mm/pageattr.c >> +++ b/arch/arm64/mm/pageattr.c >> @@ -53,6 +53,9 @@ static int change_memory_common(unsigned long addr, int >> numpages, >> WARN_ON_ONCE(1); >> } >> >> +if (!numpages) >> +return 0; >> + > Thanks for this. I can reproduce the failure on my Juno board, so I'd > like to queue this for 4.5 since it fixes a real issue. I've taken the > liberty of rebasing the arm64 part to my fixes branch and writing a > commit message. Does the patch below look ok to you? > > Will > > --->8 > > From 57adec866c0440976c96a4b8f5b59fb411b1cacb Mon Sep 17 00:00:00 2001 > From: =?UTF-8?q?Mika=20Penttil=C3=A4?= > Date: Tue, 26 Jan 2016 15:47:25 + > Subject: [PATCH] arm64: mm: avoid calling apply_to_page_range on empty range > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8 > Content-Transfer-Encoding: 8bit > > Calling apply_to_page_range with an empty range results in a BUG_ON > from the core code. This can be triggered by trying to load the st_drv > module with CONFIG_DEBUG_SET_MODULE_RONX enabled: > > kernel BUG at mm/memory.c:1874! > Internal error: Oops - BUG: 0 [#1] PREEMPT SMP > Modules linked in: > CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 > Hardware name: ARM Juno development board (r0) (DT) > task: ffc9763b8000 ti: ffc975af8000 task.ti: ffc975af8000 > PC is at apply_to_page_range+0x2cc/0x2d0 > LR is at change_memory_common+0x80/0x108 > > This patch fixes the issue by making change_memory_common (called by the > set_memory_* functions) a NOP when numpages == 0, therefore avoiding the > erroneous call to apply_to_page_range and bringing us into line with x86 > and s390. > > Cc: > Reviewed-by: Laura Abbott > Acked-by: David Rientjes > Signed-off-by: Mika Penttilä > Signed-off-by: Will Deacon > --- > arch/arm64/mm/pageattr.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c > index 3571c7309c5e..cf6240741134 100644 > --- a/arch/arm64/mm/pageattr.c > +++ b/arch/arm64/mm/pageattr.c > @@ -57,6 +57,9 @@ static int change_memory_common(unsigned long addr, int > numpages, > if (end < MODULES_VADDR || end >= MODULES_END) > return -EINVAL; > > + if (!numpages) > + return 0; > + > data.set_mask = set_mask; > data.clear_mask = clear_mask; > Yes I'm fine with that, Thanks! Mika
Re: [PATCH v2 RESEND 1/2] arm, arm64: change_memory_common with numpages == 0 should be no-op.
Hi Will, On 26.01.2016 17:59, Will Deacon wrote: > Hi Mika, > > On Tue, Jan 26, 2016 at 04:59:52PM +0200, mika.pentt...@nextfour.com wrote: >> From: Mika Penttilä>> >> This makes the caller set_memory_xx() consistent with x86. >> >> arm64 part is rebased on 4.5.0-rc1 with Ard's patch >> >> lkml.kernel.org/g/<1453125665-26627-1-git-send-email-ard.biesheu...@linaro.org> >> applied. >> >> Signed-off-by: Mika Penttilä mika.pentt...@nextfour.com >> Reviewed-by: Laura Abbott >> Acked-by: David Rientjes >> >> --- >> arch/arm/mm/pageattr.c | 3 +++ >> arch/arm64/mm/pageattr.c | 3 +++ >> 2 files changed, 6 insertions(+) >> >> diff --git a/arch/arm/mm/pageattr.c b/arch/arm/mm/pageattr.c >> index cf30daf..d19b1ad 100644 >> --- a/arch/arm/mm/pageattr.c >> +++ b/arch/arm/mm/pageattr.c >> @@ -49,6 +49,9 @@ static int change_memory_common(unsigned long addr, int >> numpages, >> WARN_ON_ONCE(1); >> } >> >> +if (!numpages) >> +return 0; >> + >> if (start < MODULES_VADDR || start >= MODULES_END) >> return -EINVAL; >> >> diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c >> index 1360a02..b582fc2 100644 >> --- a/arch/arm64/mm/pageattr.c >> +++ b/arch/arm64/mm/pageattr.c >> @@ -53,6 +53,9 @@ static int change_memory_common(unsigned long addr, int >> numpages, >> WARN_ON_ONCE(1); >> } >> >> +if (!numpages) >> +return 0; >> + > Thanks for this. I can reproduce the failure on my Juno board, so I'd > like to queue this for 4.5 since it fixes a real issue. I've taken the > liberty of rebasing the arm64 part to my fixes branch and writing a > commit message. Does the patch below look ok to you? > > Will > > --->8 > > From 57adec866c0440976c96a4b8f5b59fb411b1cacb Mon Sep 17 00:00:00 2001 > From: =?UTF-8?q?Mika=20Penttil=C3=A4?= > Date: Tue, 26 Jan 2016 15:47:25 + > Subject: [PATCH] arm64: mm: avoid calling apply_to_page_range on empty range > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8 > Content-Transfer-Encoding: 8bit > > Calling apply_to_page_range with an empty range results in a BUG_ON > from the core code. This can be triggered by trying to load the st_drv > module with CONFIG_DEBUG_SET_MODULE_RONX enabled: > > kernel BUG at mm/memory.c:1874! > Internal error: Oops - BUG: 0 [#1] PREEMPT SMP > Modules linked in: > CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 > Hardware name: ARM Juno development board (r0) (DT) > task: ffc9763b8000 ti: ffc975af8000 task.ti: ffc975af8000 > PC is at apply_to_page_range+0x2cc/0x2d0 > LR is at change_memory_common+0x80/0x108 > > This patch fixes the issue by making change_memory_common (called by the > set_memory_* functions) a NOP when numpages == 0, therefore avoiding the > erroneous call to apply_to_page_range and bringing us into line with x86 > and s390. > > Cc: > Reviewed-by: Laura Abbott > Acked-by: David Rientjes > Signed-off-by: Mika Penttilä > Signed-off-by: Will Deacon > --- > arch/arm64/mm/pageattr.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c > index 3571c7309c5e..cf6240741134 100644 > --- a/arch/arm64/mm/pageattr.c > +++ b/arch/arm64/mm/pageattr.c > @@ -57,6 +57,9 @@ static int change_memory_common(unsigned long addr, int > numpages, > if (end < MODULES_VADDR || end >= MODULES_END) > return -EINVAL; > > + if (!numpages) > + return 0; > + > data.set_mask = set_mask; > data.clear_mask = clear_mask; > Yes I'm fine with that, Thanks! Mika
Re: [PATCH v2 RESEND 1/2] arm, arm64: change_memory_common with numpages == 0 should be no-op.
On Tue, 26 Jan 2016, Will Deacon wrote: > From 57adec866c0440976c96a4b8f5b59fb411b1cacb Mon Sep 17 00:00:00 2001 > From: =?UTF-8?q?Mika=20Penttil=C3=A4?= > Date: Tue, 26 Jan 2016 15:47:25 + > Subject: [PATCH] arm64: mm: avoid calling apply_to_page_range on empty range > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8 > Content-Transfer-Encoding: 8bit > > Calling apply_to_page_range with an empty range results in a BUG_ON > from the core code. This can be triggered by trying to load the st_drv > module with CONFIG_DEBUG_SET_MODULE_RONX enabled: > > kernel BUG at mm/memory.c:1874! > Internal error: Oops - BUG: 0 [#1] PREEMPT SMP > Modules linked in: > CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 > Hardware name: ARM Juno development board (r0) (DT) > task: ffc9763b8000 ti: ffc975af8000 task.ti: ffc975af8000 > PC is at apply_to_page_range+0x2cc/0x2d0 > LR is at change_memory_common+0x80/0x108 > > This patch fixes the issue by making change_memory_common (called by the > set_memory_* functions) a NOP when numpages == 0, therefore avoiding the > erroneous call to apply_to_page_range and bringing us into line with x86 > and s390. > > Cc: > Reviewed-by: Laura Abbott > Acked-by: David Rientjes > Signed-off-by: Mika Penttilä > Signed-off-by: Will Deacon > --- > arch/arm64/mm/pageattr.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c > index 3571c7309c5e..cf6240741134 100644 > --- a/arch/arm64/mm/pageattr.c > +++ b/arch/arm64/mm/pageattr.c > @@ -57,6 +57,9 @@ static int change_memory_common(unsigned long addr, int > numpages, > if (end < MODULES_VADDR || end >= MODULES_END) > return -EINVAL; > > + if (!numpages) > + return 0; > + > data.set_mask = set_mask; > data.clear_mask = clear_mask; > LGTM, I think this issue goes back to 3.17 due to commit 11d91a770f1f ("arm64: Add CONFIG_DEBUG_SET_MODULE_RONX support") so perhaps annotate the sta...@vger.kernel.org for 3.17+.
Re: [PATCH v2 RESEND 1/2] arm, arm64: change_memory_common with numpages == 0 should be no-op.
Hi Mika, On Tue, Jan 26, 2016 at 04:59:52PM +0200, mika.pentt...@nextfour.com wrote: > From: Mika Penttilä > > This makes the caller set_memory_xx() consistent with x86. > > arm64 part is rebased on 4.5.0-rc1 with Ard's patch > > lkml.kernel.org/g/<1453125665-26627-1-git-send-email-ard.biesheu...@linaro.org> > applied. > > Signed-off-by: Mika Penttilä mika.pentt...@nextfour.com > Reviewed-by: Laura Abbott > Acked-by: David Rientjes > > --- > arch/arm/mm/pageattr.c | 3 +++ > arch/arm64/mm/pageattr.c | 3 +++ > 2 files changed, 6 insertions(+) > > diff --git a/arch/arm/mm/pageattr.c b/arch/arm/mm/pageattr.c > index cf30daf..d19b1ad 100644 > --- a/arch/arm/mm/pageattr.c > +++ b/arch/arm/mm/pageattr.c > @@ -49,6 +49,9 @@ static int change_memory_common(unsigned long addr, int > numpages, > WARN_ON_ONCE(1); > } > > + if (!numpages) > + return 0; > + > if (start < MODULES_VADDR || start >= MODULES_END) > return -EINVAL; > > diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c > index 1360a02..b582fc2 100644 > --- a/arch/arm64/mm/pageattr.c > +++ b/arch/arm64/mm/pageattr.c > @@ -53,6 +53,9 @@ static int change_memory_common(unsigned long addr, int > numpages, > WARN_ON_ONCE(1); > } > > + if (!numpages) > + return 0; > + Thanks for this. I can reproduce the failure on my Juno board, so I'd like to queue this for 4.5 since it fixes a real issue. I've taken the liberty of rebasing the arm64 part to my fixes branch and writing a commit message. Does the patch below look ok to you? Will --->8 >From 57adec866c0440976c96a4b8f5b59fb411b1cacb Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mika=20Penttil=C3=A4?= Date: Tue, 26 Jan 2016 15:47:25 + Subject: [PATCH] arm64: mm: avoid calling apply_to_page_range on empty range MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Calling apply_to_page_range with an empty range results in a BUG_ON from the core code. This can be triggered by trying to load the st_drv module with CONFIG_DEBUG_SET_MODULE_RONX enabled: kernel BUG at mm/memory.c:1874! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 Hardware name: ARM Juno development board (r0) (DT) task: ffc9763b8000 ti: ffc975af8000 task.ti: ffc975af8000 PC is at apply_to_page_range+0x2cc/0x2d0 LR is at change_memory_common+0x80/0x108 This patch fixes the issue by making change_memory_common (called by the set_memory_* functions) a NOP when numpages == 0, therefore avoiding the erroneous call to apply_to_page_range and bringing us into line with x86 and s390. Cc: Reviewed-by: Laura Abbott Acked-by: David Rientjes Signed-off-by: Mika Penttilä Signed-off-by: Will Deacon --- arch/arm64/mm/pageattr.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 3571c7309c5e..cf6240741134 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -57,6 +57,9 @@ static int change_memory_common(unsigned long addr, int numpages, if (end < MODULES_VADDR || end >= MODULES_END) return -EINVAL; + if (!numpages) + return 0; + data.set_mask = set_mask; data.clear_mask = clear_mask; -- 2.1.4
[PATCH v2 RESEND 1/2] arm, arm64: change_memory_common with numpages == 0 should be no-op.
From: Mika Penttilä This makes the caller set_memory_xx() consistent with x86. arm64 part is rebased on 4.5.0-rc1 with Ard's patch lkml.kernel.org/g/<1453125665-26627-1-git-send-email-ard.biesheu...@linaro.org> applied. Signed-off-by: Mika Penttilä mika.pentt...@nextfour.com Reviewed-by: Laura Abbott Acked-by: David Rientjes --- arch/arm/mm/pageattr.c | 3 +++ arch/arm64/mm/pageattr.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/arch/arm/mm/pageattr.c b/arch/arm/mm/pageattr.c index cf30daf..d19b1ad 100644 --- a/arch/arm/mm/pageattr.c +++ b/arch/arm/mm/pageattr.c @@ -49,6 +49,9 @@ static int change_memory_common(unsigned long addr, int numpages, WARN_ON_ONCE(1); } + if (!numpages) + return 0; + if (start < MODULES_VADDR || start >= MODULES_END) return -EINVAL; diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 1360a02..b582fc2 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -53,6 +53,9 @@ static int change_memory_common(unsigned long addr, int numpages, WARN_ON_ONCE(1); } + if (!numpages) + return 0; + /* * Kernel VA mappings are always live, and splitting live section * mappings into page mappings may cause TLB conflicts. This means -- 1.9.1
[PATCH v2 RESEND 1/2] arm, arm64: change_memory_common with numpages == 0 should be no-op.
From: Mika PenttiläThis makes the caller set_memory_xx() consistent with x86. arm64 part is rebased on 4.5.0-rc1 with Ard's patch lkml.kernel.org/g/<1453125665-26627-1-git-send-email-ard.biesheu...@linaro.org> applied. Signed-off-by: Mika Penttilä mika.pentt...@nextfour.com Reviewed-by: Laura Abbott Acked-by: David Rientjes --- arch/arm/mm/pageattr.c | 3 +++ arch/arm64/mm/pageattr.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/arch/arm/mm/pageattr.c b/arch/arm/mm/pageattr.c index cf30daf..d19b1ad 100644 --- a/arch/arm/mm/pageattr.c +++ b/arch/arm/mm/pageattr.c @@ -49,6 +49,9 @@ static int change_memory_common(unsigned long addr, int numpages, WARN_ON_ONCE(1); } + if (!numpages) + return 0; + if (start < MODULES_VADDR || start >= MODULES_END) return -EINVAL; diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 1360a02..b582fc2 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -53,6 +53,9 @@ static int change_memory_common(unsigned long addr, int numpages, WARN_ON_ONCE(1); } + if (!numpages) + return 0; + /* * Kernel VA mappings are always live, and splitting live section * mappings into page mappings may cause TLB conflicts. This means -- 1.9.1
Re: [PATCH v2 RESEND 1/2] arm, arm64: change_memory_common with numpages == 0 should be no-op.
Hi Mika, On Tue, Jan 26, 2016 at 04:59:52PM +0200, mika.pentt...@nextfour.com wrote: > From: Mika Penttilä> > This makes the caller set_memory_xx() consistent with x86. > > arm64 part is rebased on 4.5.0-rc1 with Ard's patch > > lkml.kernel.org/g/<1453125665-26627-1-git-send-email-ard.biesheu...@linaro.org> > applied. > > Signed-off-by: Mika Penttilä mika.pentt...@nextfour.com > Reviewed-by: Laura Abbott > Acked-by: David Rientjes > > --- > arch/arm/mm/pageattr.c | 3 +++ > arch/arm64/mm/pageattr.c | 3 +++ > 2 files changed, 6 insertions(+) > > diff --git a/arch/arm/mm/pageattr.c b/arch/arm/mm/pageattr.c > index cf30daf..d19b1ad 100644 > --- a/arch/arm/mm/pageattr.c > +++ b/arch/arm/mm/pageattr.c > @@ -49,6 +49,9 @@ static int change_memory_common(unsigned long addr, int > numpages, > WARN_ON_ONCE(1); > } > > + if (!numpages) > + return 0; > + > if (start < MODULES_VADDR || start >= MODULES_END) > return -EINVAL; > > diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c > index 1360a02..b582fc2 100644 > --- a/arch/arm64/mm/pageattr.c > +++ b/arch/arm64/mm/pageattr.c > @@ -53,6 +53,9 @@ static int change_memory_common(unsigned long addr, int > numpages, > WARN_ON_ONCE(1); > } > > + if (!numpages) > + return 0; > + Thanks for this. I can reproduce the failure on my Juno board, so I'd like to queue this for 4.5 since it fixes a real issue. I've taken the liberty of rebasing the arm64 part to my fixes branch and writing a commit message. Does the patch below look ok to you? Will --->8 >From 57adec866c0440976c96a4b8f5b59fb411b1cacb Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mika=20Penttil=C3=A4?= Date: Tue, 26 Jan 2016 15:47:25 + Subject: [PATCH] arm64: mm: avoid calling apply_to_page_range on empty range MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Calling apply_to_page_range with an empty range results in a BUG_ON from the core code. This can be triggered by trying to load the st_drv module with CONFIG_DEBUG_SET_MODULE_RONX enabled: kernel BUG at mm/memory.c:1874! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 Hardware name: ARM Juno development board (r0) (DT) task: ffc9763b8000 ti: ffc975af8000 task.ti: ffc975af8000 PC is at apply_to_page_range+0x2cc/0x2d0 LR is at change_memory_common+0x80/0x108 This patch fixes the issue by making change_memory_common (called by the set_memory_* functions) a NOP when numpages == 0, therefore avoiding the erroneous call to apply_to_page_range and bringing us into line with x86 and s390. Cc: Reviewed-by: Laura Abbott Acked-by: David Rientjes Signed-off-by: Mika Penttilä Signed-off-by: Will Deacon --- arch/arm64/mm/pageattr.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 3571c7309c5e..cf6240741134 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -57,6 +57,9 @@ static int change_memory_common(unsigned long addr, int numpages, if (end < MODULES_VADDR || end >= MODULES_END) return -EINVAL; + if (!numpages) + return 0; + data.set_mask = set_mask; data.clear_mask = clear_mask; -- 2.1.4
Re: [PATCH v2 RESEND 1/2] arm, arm64: change_memory_common with numpages == 0 should be no-op.
On Tue, 26 Jan 2016, Will Deacon wrote: > From 57adec866c0440976c96a4b8f5b59fb411b1cacb Mon Sep 17 00:00:00 2001 > From: =?UTF-8?q?Mika=20Penttil=C3=A4?=> Date: Tue, 26 Jan 2016 15:47:25 + > Subject: [PATCH] arm64: mm: avoid calling apply_to_page_range on empty range > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8 > Content-Transfer-Encoding: 8bit > > Calling apply_to_page_range with an empty range results in a BUG_ON > from the core code. This can be triggered by trying to load the st_drv > module with CONFIG_DEBUG_SET_MODULE_RONX enabled: > > kernel BUG at mm/memory.c:1874! > Internal error: Oops - BUG: 0 [#1] PREEMPT SMP > Modules linked in: > CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 > Hardware name: ARM Juno development board (r0) (DT) > task: ffc9763b8000 ti: ffc975af8000 task.ti: ffc975af8000 > PC is at apply_to_page_range+0x2cc/0x2d0 > LR is at change_memory_common+0x80/0x108 > > This patch fixes the issue by making change_memory_common (called by the > set_memory_* functions) a NOP when numpages == 0, therefore avoiding the > erroneous call to apply_to_page_range and bringing us into line with x86 > and s390. > > Cc: > Reviewed-by: Laura Abbott > Acked-by: David Rientjes > Signed-off-by: Mika Penttilä > Signed-off-by: Will Deacon > --- > arch/arm64/mm/pageattr.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c > index 3571c7309c5e..cf6240741134 100644 > --- a/arch/arm64/mm/pageattr.c > +++ b/arch/arm64/mm/pageattr.c > @@ -57,6 +57,9 @@ static int change_memory_common(unsigned long addr, int > numpages, > if (end < MODULES_VADDR || end >= MODULES_END) > return -EINVAL; > > + if (!numpages) > + return 0; > + > data.set_mask = set_mask; > data.clear_mask = clear_mask; > LGTM, I think this issue goes back to 3.17 due to commit 11d91a770f1f ("arm64: Add CONFIG_DEBUG_SET_MODULE_RONX support") so perhaps annotate the sta...@vger.kernel.org for 3.17+.