| Message ID | defab86b7fb897c88a05a33b62ccf38467dda884.1724747058.git.christophe.leroy@csgroup.eu (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | random: vDSO: Redefine PAGE_SIZE and PAGE_MASK | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/github-powerpc_sparse | success | Successfully ran 4 jobs. |
| snowpatch_ozlabs/github-powerpc_clang | success | Successfully ran 5 jobs. |
| snowpatch_ozlabs/github-powerpc_kernel_qemu | success | Successfully ran 21 jobs. |
I don't love this, but it might be the lesser of evils, so sure, let's do it. I think I'll combine these header fixups so that the whole operation is a bit more clear. The commit is still pretty small. Something like below: From 0d9a3d68cd6222395a605abd0ac625c41d4cabfa Mon Sep 17 00:00:00 2001 From: Christophe Leroy <christophe.leroy@csgroup.eu> Date: Tue, 27 Aug 2024 09:31:47 +0200 Subject: [PATCH] random: vDSO: clean header inclusion in getrandom Depending on the architecture, building a 32-bit vDSO on a 64-bit kernel is problematic when some system headers are included. Minimise the amount of headers by moving needed items, such as __{get,put}_unaligned_t, into dedicated common headers and in general use more specific headers, similar to what was done in commit 8165b57bca21 ("linux/const.h: Extract common header for vDSO") and commit 8c59ab839f52 ("lib/vdso: Enable common headers"). On some architectures this results in missing PAGE_SIZE, as was described by commit 8b3843ae3634 ("vdso/datapage: Quick fix - use asm/page-def.h for ARM64"), so define this if necessary, in the same way as done prior by commit cffaefd15a8f ("vdso: Use CONFIG_PAGE_SHIFT in vdso/datapage.h"). Removing linux/time64.h leads to missing 'struct timespec64' in x86's asm/pvclock.h. Add a forward declaration of that struct in that file. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> --- arch/x86/include/asm/pvclock.h | 1 + include/asm-generic/unaligned.h | 11 +---------- include/vdso/helpers.h | 1 + include/vdso/unaligned.h | 15 +++++++++++++++ lib/vdso/getrandom.c | 13 ++++++++----- 5 files changed, 26 insertions(+), 15 deletions(-) create mode 100644 include/vdso/unaligned.h diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h index 0c92db84469d..6e4f8fae3ce9 100644 --- a/arch/x86/include/asm/pvclock.h +++ b/arch/x86/include/asm/pvclock.h @@ -5,6 +5,7 @@ #include <asm/clocksource.h> #include <asm/pvclock-abi.h> +struct timespec64; /* some helper functions for xen and kvm pv clock sources */ u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src); u64 pvclock_clocksource_read_nowd(struct pvclock_vcpu_time_info *src); diff --git a/include/asm-generic/unaligned.h b/include/asm-generic/unaligned.h index a84c64e5f11e..95acdd70b3b2 100644 --- a/include/asm-generic/unaligned.h +++ b/include/asm-generic/unaligned.h @@ -8,16 +8,7 @@ */ #include <linux/unaligned/packed_struct.h> #include <asm/byteorder.h> - -#define __get_unaligned_t(type, ptr) ({ \ - const struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ - __pptr->x; \ -}) - -#define __put_unaligned_t(type, val, ptr) do { \ - struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ - __pptr->x = (val); \ -} while (0) +#include <vdso/unaligned.h> #define get_unaligned(ptr) __get_unaligned_t(typeof(*(ptr)), (ptr)) #define put_unaligned(val, ptr) __put_unaligned_t(typeof(*(ptr)), (val), (ptr)) diff --git a/include/vdso/helpers.h b/include/vdso/helpers.h index 73501149439d..3ddb03bb05cb 100644 --- a/include/vdso/helpers.h +++ b/include/vdso/helpers.h @@ -4,6 +4,7 @@ #ifndef __ASSEMBLY__ +#include <asm/barrier.h> #include <vdso/datapage.h> static __always_inline u32 vdso_read_begin(const struct vdso_data *vd) diff --git a/include/vdso/unaligned.h b/include/vdso/unaligned.h new file mode 100644 index 000000000000..eee3d2a4dbe4 --- /dev/null +++ b/include/vdso/unaligned.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __VDSO_UNALIGNED_H +#define __VDSO_UNALIGNED_H + +#define __get_unaligned_t(type, ptr) ({ \ + const struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ + __pptr->x; \ +}) + +#define __put_unaligned_t(type, val, ptr) do { \ + struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ + __pptr->x = (val); \ +} while (0) + +#endif /* __VDSO_UNALIGNED_H */ diff --git a/lib/vdso/getrandom.c b/lib/vdso/getrandom.c index 1281fa3546c2..938ca539aaa6 100644 --- a/lib/vdso/getrandom.c +++ b/lib/vdso/getrandom.c @@ -4,15 +4,18 @@ */ #include <linux/array_size.h> -#include <linux/cache.h> -#include <linux/kernel.h> -#include <linux/time64.h> +#include <linux/minmax.h> #include <vdso/datapage.h> #include <vdso/getrandom.h> +#include <vdso/unaligned.h> #include <asm/vdso/getrandom.h> -#include <asm/vdso/vsyscall.h> -#include <asm/unaligned.h> #include <uapi/linux/mman.h> +#include <uapi/linux/random.h> + +#undef PAGE_SIZE +#undef PAGE_MASK +#define PAGE_SIZE (1UL << CONFIG_PAGE_SHIFT) +#define PAGE_MASK (~(PAGE_SIZE - 1)) #define MEMCPY_AND_ZERO_SRC(type, dst, src, len) do { \ while (len >= sizeof(type)) { \ -- 2.46.0
Le 27/08/2024 à 10:40, Jason A. Donenfeld a écrit : > I don't love this, but it might be the lesser of evils, so sure, let's > do it. I don't love it either but I still prefer it to: #ifndef PAGE_SIZE #define PAGE_SIZE #define PAGE_MASK #endif At least we are sure that every architecture get the same , independant of the selected options, and we know what we get. For instance, on x86, when you select CONFIG_HYPERV_TIMER you get asm/hyperv_timer.h which indirectly pulls page.h. But when CONFIG_HYPERV_TIMER is not selected you don't get asm/hyperv_timer.h > > I think I'll combine these header fixups so that the whole operation is > a bit more clear. The commit is still pretty small. Something like > below: Looks good to me. Thanks Christophe > > From 0d9a3d68cd6222395a605abd0ac625c41d4cabfa Mon Sep 17 00:00:00 2001 > From: Christophe Leroy <christophe.leroy@csgroup.eu> > Date: Tue, 27 Aug 2024 09:31:47 +0200 > Subject: [PATCH] random: vDSO: clean header inclusion in getrandom > > Depending on the architecture, building a 32-bit vDSO on a 64-bit kernel > is problematic when some system headers are included. > > Minimise the amount of headers by moving needed items, such as > __{get,put}_unaligned_t, into dedicated common headers and in general > use more specific headers, similar to what was done in commit > 8165b57bca21 ("linux/const.h: Extract common header for vDSO") and > commit 8c59ab839f52 ("lib/vdso: Enable common headers"). > > On some architectures this results in missing PAGE_SIZE, as was > described by commit 8b3843ae3634 ("vdso/datapage: Quick fix - use > asm/page-def.h for ARM64"), so define this if necessary, in the same way > as done prior by commit cffaefd15a8f ("vdso: Use CONFIG_PAGE_SHIFT in > vdso/datapage.h"). > > Removing linux/time64.h leads to missing 'struct timespec64' in > x86's asm/pvclock.h. Add a forward declaration of that struct in > that file. > > Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> > --- > arch/x86/include/asm/pvclock.h | 1 + > include/asm-generic/unaligned.h | 11 +---------- > include/vdso/helpers.h | 1 + > include/vdso/unaligned.h | 15 +++++++++++++++ > lib/vdso/getrandom.c | 13 ++++++++----- > 5 files changed, 26 insertions(+), 15 deletions(-) > create mode 100644 include/vdso/unaligned.h > > diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h > index 0c92db84469d..6e4f8fae3ce9 100644 > --- a/arch/x86/include/asm/pvclock.h > +++ b/arch/x86/include/asm/pvclock.h > @@ -5,6 +5,7 @@ > #include <asm/clocksource.h> > #include <asm/pvclock-abi.h> > > +struct timespec64; > /* some helper functions for xen and kvm pv clock sources */ > u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src); > u64 pvclock_clocksource_read_nowd(struct pvclock_vcpu_time_info *src); > diff --git a/include/asm-generic/unaligned.h b/include/asm-generic/unaligned.h > index a84c64e5f11e..95acdd70b3b2 100644 > --- a/include/asm-generic/unaligned.h > +++ b/include/asm-generic/unaligned.h > @@ -8,16 +8,7 @@ > */ > #include <linux/unaligned/packed_struct.h> > #include <asm/byteorder.h> > - > -#define __get_unaligned_t(type, ptr) ({ \ > - const struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ > - __pptr->x; \ > -}) > - > -#define __put_unaligned_t(type, val, ptr) do { \ > - struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ > - __pptr->x = (val); \ > -} while (0) > +#include <vdso/unaligned.h> > > #define get_unaligned(ptr) __get_unaligned_t(typeof(*(ptr)), (ptr)) > #define put_unaligned(val, ptr) __put_unaligned_t(typeof(*(ptr)), (val), (ptr)) > diff --git a/include/vdso/helpers.h b/include/vdso/helpers.h > index 73501149439d..3ddb03bb05cb 100644 > --- a/include/vdso/helpers.h > +++ b/include/vdso/helpers.h > @@ -4,6 +4,7 @@ > > #ifndef __ASSEMBLY__ > > +#include <asm/barrier.h> > #include <vdso/datapage.h> > > static __always_inline u32 vdso_read_begin(const struct vdso_data *vd) > diff --git a/include/vdso/unaligned.h b/include/vdso/unaligned.h > new file mode 100644 > index 000000000000..eee3d2a4dbe4 > --- /dev/null > +++ b/include/vdso/unaligned.h > @@ -0,0 +1,15 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +#ifndef __VDSO_UNALIGNED_H > +#define __VDSO_UNALIGNED_H > + > +#define __get_unaligned_t(type, ptr) ({ \ > + const struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ > + __pptr->x; \ > +}) > + > +#define __put_unaligned_t(type, val, ptr) do { \ > + struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \ > + __pptr->x = (val); \ > +} while (0) > + > +#endif /* __VDSO_UNALIGNED_H */ > diff --git a/lib/vdso/getrandom.c b/lib/vdso/getrandom.c > index 1281fa3546c2..938ca539aaa6 100644 > --- a/lib/vdso/getrandom.c > +++ b/lib/vdso/getrandom.c > @@ -4,15 +4,18 @@ > */ > > #include <linux/array_size.h> > -#include <linux/cache.h> > -#include <linux/kernel.h> > -#include <linux/time64.h> > +#include <linux/minmax.h> > #include <vdso/datapage.h> > #include <vdso/getrandom.h> > +#include <vdso/unaligned.h> > #include <asm/vdso/getrandom.h> > -#include <asm/vdso/vsyscall.h> > -#include <asm/unaligned.h> > #include <uapi/linux/mman.h> > +#include <uapi/linux/random.h> > + > +#undef PAGE_SIZE > +#undef PAGE_MASK > +#define PAGE_SIZE (1UL << CONFIG_PAGE_SHIFT) > +#define PAGE_MASK (~(PAGE_SIZE - 1)) > > #define MEMCPY_AND_ZERO_SRC(type, dst, src, len) do { \ > while (len >= sizeof(type)) { \ > -- > 2.46.0
On Tue, Aug 27, 2024, at 10:40, Jason A. Donenfeld wrote: > I don't love this, but it might be the lesser of evils, so sure, let's > do it. > > I think I'll combine these header fixups so that the whole operation is > a bit more clear. The commit is still pretty small. Something like > below: > > From 0d9a3d68cd6222395a605abd0ac625c41d4cabfa Mon Sep 17 00:00:00 2001 > From: Christophe Leroy <christophe.leroy@csgroup.eu> > Date: Tue, 27 Aug 2024 09:31:47 +0200 > Subject: [PATCH] random: vDSO: clean header inclusion in getrandom > > Depending on the architecture, building a 32-bit vDSO on a 64-bit kernel > is problematic when some system headers are included. > > Minimise the amount of headers by moving needed items, such as > __{get,put}_unaligned_t, into dedicated common headers and in general > use more specific headers, similar to what was done in commit > 8165b57bca21 ("linux/const.h: Extract common header for vDSO") and > commit 8c59ab839f52 ("lib/vdso: Enable common headers"). > > On some architectures this results in missing PAGE_SIZE, as was > described by commit 8b3843ae3634 ("vdso/datapage: Quick fix - use > asm/page-def.h for ARM64"), so define this if necessary, in the same way > as done prior by commit cffaefd15a8f ("vdso: Use CONFIG_PAGE_SHIFT in > vdso/datapage.h"). > > Removing linux/time64.h leads to missing 'struct timespec64' in > x86's asm/pvclock.h. Add a forward declaration of that struct in > that file. > > Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> This is clearly better, but there are still a couple of inaccuracies that may end up biting us again later. Not sure whether it's worth trying to fix it all at once or if we want to address them when that happens: > #include <linux/array_size.h> > -#include <linux/cache.h> > -#include <linux/kernel.h> > -#include <linux/time64.h> > +#include <linux/minmax.h> These are still two headers outside of the vdso/ namespace. For arm64 we had concluded that this is never safe, and any vdso header should only include other vdso headers so we never pull in anything that e.g. depends on memory management headers that are in turn broken for the compat vdso. The array_size.h header is really small, so that one could probably just be moved into the vdso/ namespace. The minmax.h header is already rather complex, so it may be better to just open-code the usage of MIN/MAX where needed? > #include <vdso/datapage.h> > #include <vdso/getrandom.h> > +#include <vdso/unaligned.h> > #include <asm/vdso/getrandom.h> > -#include <asm/vdso/vsyscall.h> > -#include <asm/unaligned.h> > #include <uapi/linux/mman.h> > +#include <uapi/linux/random.h> > + > +#undef PAGE_SIZE > +#undef PAGE_MASK > +#define PAGE_SIZE (1UL << CONFIG_PAGE_SHIFT) > +#define PAGE_MASK (~(PAGE_SIZE - 1)) Since these are now the same across all architectures, maybe we can just have the PAGE_SIZE definitions a vdso header instead and include that from asm/page.h. Including uapi/linux/mman.h may still be problematic on some architectures if they change it in a way that is incompatible with compat vdso, but at least that can't accidentally rely on CONFIG_64BIT or something else that would be wrong there. Arnd
Le 27/08/2024 à 11:59, Arnd Bergmann a écrit : > On Tue, Aug 27, 2024, at 10:40, Jason A. Donenfeld wrote: >> I don't love this, but it might be the lesser of evils, so sure, let's >> do it. >> >> I think I'll combine these header fixups so that the whole operation is >> a bit more clear. The commit is still pretty small. Something like >> below: >> >> From 0d9a3d68cd6222395a605abd0ac625c41d4cabfa Mon Sep 17 00:00:00 2001 >> From: Christophe Leroy <christophe.leroy@csgroup.eu> >> Date: Tue, 27 Aug 2024 09:31:47 +0200 >> Subject: [PATCH] random: vDSO: clean header inclusion in getrandom >> >> Depending on the architecture, building a 32-bit vDSO on a 64-bit kernel >> is problematic when some system headers are included. >> >> Minimise the amount of headers by moving needed items, such as >> __{get,put}_unaligned_t, into dedicated common headers and in general >> use more specific headers, similar to what was done in commit >> 8165b57bca21 ("linux/const.h: Extract common header for vDSO") and >> commit 8c59ab839f52 ("lib/vdso: Enable common headers"). >> >> On some architectures this results in missing PAGE_SIZE, as was >> described by commit 8b3843ae3634 ("vdso/datapage: Quick fix - use >> asm/page-def.h for ARM64"), so define this if necessary, in the same way >> as done prior by commit cffaefd15a8f ("vdso: Use CONFIG_PAGE_SHIFT in >> vdso/datapage.h"). >> >> Removing linux/time64.h leads to missing 'struct timespec64' in >> x86's asm/pvclock.h. Add a forward declaration of that struct in >> that file. >> >> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> >> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> > > This is clearly better, but there are still a couple of inaccuracies > that may end up biting us again later. Not sure whether it's worth > trying to fix it all at once or if we want to address them when that > happens: > >> #include <linux/array_size.h> >> -#include <linux/cache.h> >> -#include <linux/kernel.h> >> -#include <linux/time64.h> >> +#include <linux/minmax.h> > > These are still two headers outside of the vdso/ namespace. For arm64 > we had concluded that this is never safe, and any vdso header should > only include other vdso headers so we never pull in anything that > e.g. depends on memory management headers that are in turn broken > for the compat vdso. > > The array_size.h header is really small, so that one could > probably just be moved into the vdso/ namespace. The minmax.h > header is already rather complex, so it may be better to just > open-code the usage of MIN/MAX where needed? It is used at two places only so yes can to that. Same for ARRAY_SIZE(->reserved) by the way, easy to do opencode, we also have it only once > >> #include <vdso/datapage.h> >> #include <vdso/getrandom.h> >> +#include <vdso/unaligned.h> >> #include <asm/vdso/getrandom.h> >> -#include <asm/vdso/vsyscall.h> >> -#include <asm/unaligned.h> >> #include <uapi/linux/mman.h> >> +#include <uapi/linux/random.h> >> + >> +#undef PAGE_SIZE >> +#undef PAGE_MASK >> +#define PAGE_SIZE (1UL << CONFIG_PAGE_SHIFT) >> +#define PAGE_MASK (~(PAGE_SIZE - 1)) > > Since these are now the same across all architectures, maybe we > can just have the PAGE_SIZE definitions a vdso header instead > and include that from asm/page.h. I gave it a quick look yesterday, there are still some subtleties between architectures. For instance, most architectures use 1UL for the shift but powerpc use 1 and has the following comment: /* * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we * assign PAGE_MASK to a larger type it gets extended the way we want * (i.e. with 1s in the high bits) */ So we'll have to look at all this carefully when we want something common, or am I missing something ? > > Including uapi/linux/mman.h may still be problematic on > some architectures if they change it in a way that is > incompatible with compat vdso, but at least that can't > accidentally rely on CONFIG_64BIT or something else that > would be wrong there. Yes that one is tricky. Because uapi/linux/mman.h includes asm/mman.h with the intention to include uapi/asm/mman.h but when built from the kernel in reality you get arch/powerpc/include/asm/mman.h and I had to add some ifdefery to kick-out kernel oddities it contains that pull additional kernel headers. diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h index 17a77d47ed6d..42a51a993d94 100644 --- a/arch/powerpc/include/asm/mman.h +++ b/arch/powerpc/include/asm/mman.h @@ -6,7 +6,7 @@ #include <uapi/asm/mman.h> -#ifdef CONFIG_PPC64 +#if defined(CONFIG_PPC64) && !defined(BUILD_VDSO) #include <asm/cputable.h> #include <linux/mm.h> Christophe
Hi Christophe, On 27/08/2024 11:49, Christophe Leroy wrote: ... >> >> These are still two headers outside of the vdso/ namespace. For arm64 >> we had concluded that this is never safe, and any vdso header should >> only include other vdso headers so we never pull in anything that >> e.g. depends on memory management headers that are in turn broken >> for the compat vdso. >> >> The array_size.h header is really small, so that one could >> probably just be moved into the vdso/ namespace. The minmax.h >> header is already rather complex, so it may be better to just >> open-code the usage of MIN/MAX where needed? > > It is used at two places only so yes can to that. > Could you please clarify where minmax is needed? I tried to build Jason's master tree for x86, commenting the header and it seems building fine. I might be missing something. > Same for ARRAY_SIZE(->reserved) by the way, easy to do opencode, we also have it > only once > I have a similar issue to figure out why linux/array_size.h and uapi/linux/random.h are needed. It seems that I can build the object without them. Could you please explain? In general, the philosophy adopted to split the headers is to extract the set of functions used by vDSOs from the linux headers and place them in the vdso headers. Consequently the linux header includes to vdso one. E.g.: linux/time64.h includes vdso/time64.h. IMHO we should follow the same approach, if at all for consistency, unless there is a valid reason. ... >> >> Including uapi/linux/mman.h may still be problematic on >> some architectures if they change it in a way that is >> incompatible with compat vdso, but at least that can't >> accidentally rely on CONFIG_64BIT or something else that >> would be wrong there. > > Yes that one is tricky. Because uapi/linux/mman.h includes asm/mman.h with the > intention to include uapi/asm/mman.h but when built from the kernel in reality > you get arch/powerpc/include/asm/mman.h and I had to add some ifdefery to > kick-out kernel oddities it contains that pull additional kernel headers. > > diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h > index 17a77d47ed6d..42a51a993d94 100644 > --- a/arch/powerpc/include/asm/mman.h > +++ b/arch/powerpc/include/asm/mman.h > @@ -6,7 +6,7 @@ > > #include <uapi/asm/mman.h> > > -#ifdef CONFIG_PPC64 > +#if defined(CONFIG_PPC64) && !defined(BUILD_VDSO) > > #include <asm/cputable.h> > #include <linux/mm.h> > I agree with Arnd here. uapi/linux/mman.h can cause us problems in the long run. I am attaching a patch to provide my view on how to minimize the headers included and use only the vdso/ namespace. Please, before using the code, consider that I conducted very limited testing. Note: It should apply clean on Jason's tree. Let me know your thoughts. > > Christophe
Le 27/08/2024 à 18:05, Vincenzo Frascino a écrit : > Hi Christophe, > > On 27/08/2024 11:49, Christophe Leroy wrote: > > ... > > >>> >>> These are still two headers outside of the vdso/ namespace. For arm64 >>> we had concluded that this is never safe, and any vdso header should >>> only include other vdso headers so we never pull in anything that >>> e.g. depends on memory management headers that are in turn broken >>> for the compat vdso. >>> >>> The array_size.h header is really small, so that one could >>> probably just be moved into the vdso/ namespace. The minmax.h >>> header is already rather complex, so it may be better to just >>> open-code the usage of MIN/MAX where needed? >> >> It is used at two places only so yes can to that. >> > > Could you please clarify where minmax is needed? I tried to build Jason's master > tree for x86, commenting the header and it seems building fine. I might be > missing something. Without it: VDSO32C arch/powerpc/kernel/vdso/vgetrandom-32.o In file included from /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:11, from <command-line>: ./arch/powerpc/include/asm/vdso/getrandom.h: In function '__arch_get_vdso_rng_data': ./arch/powerpc/include/asm/vdso/getrandom.h:46:9: error: implicit declaration of function 'BUILD_BUG' [-Werror=implicit-function-declaration] 46 | BUILD_BUG(); | ^~~~~~~~~ ./arch/powerpc/include/asm/vdso/getrandom.h:47:1: error: no return statement in function returning non-void [-Werror=return-type] 47 | } | ^ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c: In function '__cvdso_getrandom_data': /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:76:23: error: implicit declaration of function 'min_t' [-Werror=implicit-function-declaration] 76 | ssize_t ret = min_t(size_t, INT_MAX & PAGE_MASK /* = MAX_RW_COUNT */, len); | ^~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:76:29: error: expected expression before 'size_t' 76 | ssize_t ret = min_t(size_t, INT_MAX & PAGE_MASK /* = MAX_RW_COUNT */, len); | ^~~~~~ In file included from ./include/linux/array_size.h:5, from /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:6: ./include/linux/compiler.h:243:33: error: implicit declaration of function 'BUILD_BUG_ON_ZERO' [-Werror=implicit-function-declaration] 243 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) | ^~~~~~~~~~~~~~~~~ ./include/linux/array_size.h:11:59: note: in expansion of macro '__must_be_array' 11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) | ^~~~~~~~~~~~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:40: note: in expansion of macro 'ARRAY_SIZE' 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~~~~~~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:196:27: error: expected expression before 'size_t' 196 | batch_len = min_t(size_t, sizeof(state->batch) - state->pos, len); | ^~~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:247:9: error: implicit declaration of function 'BUILD_BUG_ON' [-Werror=implicit-function-declaration] 247 | BUILD_BUG_ON(sizeof(state->batch_key) % CHACHA_BLOCK_SIZE != 0); | ^~~~~~~~~~~~ cc1: some warnings being treated as errors make[2]: *** [arch/powerpc/kernel/vdso/Makefile:93: arch/powerpc/kernel/vdso/vgetrandom-32.o] Error 1 make[1]: *** [arch/powerpc/Makefile:388: vdso_prepare] Error 2 make: *** [Makefile:224: __sub-make] Error 2 > >> Same for ARRAY_SIZE(->reserved) by the way, easy to do opencode, we also have it >> only once >> > > I have a similar issue to figure out why linux/array_size.h and > uapi/linux/random.h are needed. It seems that I can build the object without > them. Could you please explain? Without linux/array_size.h: VDSO32C arch/powerpc/kernel/vdso/vgetrandom-32.o In file included from <command-line>: /home/chleroy/linux-powerpc/lib/vdso/getrandom.c: In function '__cvdso_getrandom_data': /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:40: error: implicit declaration of function 'ARRAY_SIZE' [-Werror=implicit-function-declaration] 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~~~~~~~~~ cc1: some warnings being treated as errors make[2]: *** [arch/powerpc/kernel/vdso/Makefile:93: arch/powerpc/kernel/vdso/vgetrandom-32.o] Error 1 make[1]: *** [arch/powerpc/Makefile:388: vdso_prepare] Error 2 make: *** [Makefile:224: __sub-make] Error 2 Without uapi/linux/random.h: VDSO32C arch/powerpc/kernel/vdso/vgetrandom-32.o In file included from <command-line>: /home/chleroy/linux-powerpc/lib/vdso/getrandom.c: In function '__cvdso_getrandom_data': /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:86:23: error: invalid use of undefined type 'struct vgetrandom_opaque_params' 86 | params->size_of_opaque_state = sizeof(*state); | ^~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:87:23: error: invalid use of undefined type 'struct vgetrandom_opaque_params' 87 | params->mmap_prot = PROT_READ | PROT_WRITE; | ^~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:88:23: error: invalid use of undefined type 'struct vgetrandom_opaque_params' 88 | params->mmap_flags = MAP_DROPPABLE | MAP_ANONYMOUS; | ^~ In file included from /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:6: /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:57: error: invalid use of undefined type 'struct vgetrandom_opaque_params' 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~ ./include/linux/array_size.h:11:33: note: in definition of macro 'ARRAY_SIZE' 11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) | ^~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:57: error: invalid use of undefined type 'struct vgetrandom_opaque_params' 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~ ./include/linux/array_size.h:11:48: note: in definition of macro 'ARRAY_SIZE' 11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) | ^~~ In file included from ./include/linux/minmax.h:5, from /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:7: /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:57: error: invalid use of undefined type 'struct vgetrandom_opaque_params' 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~ ./include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO' 16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); }))) | ^ ./include/linux/compiler.h:243:51: note: in expansion of macro '__same_type' 243 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) | ^~~~~~~~~~~ ./include/linux/array_size.h:11:59: note: in expansion of macro '__must_be_array' 11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) | ^~~~~~~~~~~~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:40: note: in expansion of macro 'ARRAY_SIZE' 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~~~~~~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:57: error: invalid use of undefined type 'struct vgetrandom_opaque_params' 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~ ./include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO' 16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); }))) | ^ ./include/linux/compiler.h:243:51: note: in expansion of macro '__same_type' 243 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) | ^~~~~~~~~~~ ./include/linux/array_size.h:11:59: note: in expansion of macro '__must_be_array' 11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) | ^~~~~~~~~~~~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:40: note: in expansion of macro 'ARRAY_SIZE' 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~~~~~~~~~ ./include/linux/build_bug.h:16:51: error: bit-field '<anonymous>' width not an integer constant 16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); }))) | ^ ./include/linux/compiler.h:243:33: note: in expansion of macro 'BUILD_BUG_ON_ZERO' 243 | #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) | ^~~~~~~~~~~~~~~~~ ./include/linux/array_size.h:11:59: note: in expansion of macro '__must_be_array' 11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) | ^~~~~~~~~~~~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:40: note: in expansion of macro 'ARRAY_SIZE' 89 | for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i) | ^~~~~~~~~~ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:90:31: error: invalid use of undefined type 'struct vgetrandom_opaque_params' 90 | params->reserved[i] = 0; | ^~ In file included from ./include/linux/array_size.h:5: /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:99:32: error: 'GRND_NONBLOCK' undeclared (first use in this function); did you mean 'MAP_NONBLOCK'? 99 | if (unlikely(flags & ~(GRND_NONBLOCK | GRND_RANDOM | GRND_INSECURE))) | ^~~~~~~~~~~~~ ./include/linux/compiler.h:77:45: note: in definition of macro 'unlikely' 77 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:99:32: note: each undeclared identifier is reported only once for each function it appears in 99 | if (unlikely(flags & ~(GRND_NONBLOCK | GRND_RANDOM | GRND_INSECURE))) | ^~~~~~~~~~~~~ ./include/linux/compiler.h:77:45: note: in definition of macro 'unlikely' 77 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:99:48: error: 'GRND_RANDOM' undeclared (first use in this function) 99 | if (unlikely(flags & ~(GRND_NONBLOCK | GRND_RANDOM | GRND_INSECURE))) | ^~~~~~~~~~~ ./include/linux/compiler.h:77:45: note: in definition of macro 'unlikely' 77 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:99:62: error: 'GRND_INSECURE' undeclared (first use in this function) 99 | if (unlikely(flags & ~(GRND_NONBLOCK | GRND_RANDOM | GRND_INSECURE))) | ^~~~~~~~~~~~~ ./include/linux/compiler.h:77:45: note: in definition of macro 'unlikely' 77 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ make[2]: *** [arch/powerpc/kernel/vdso/Makefile:93: arch/powerpc/kernel/vdso/vgetrandom-32.o] Error 1 make[1]: *** [arch/powerpc/Makefile:388: vdso_prepare] Error 2 make: *** [Makefile:224: __sub-make] Error 2 > > In general, the philosophy adopted to split the headers is to extract the set of > functions used by vDSOs from the linux headers and place them in the vdso headers. > Consequently the linux header includes to vdso one. E.g.: linux/time64.h > includes vdso/time64.h. > > IMHO we should follow the same approach, if at all for consistency, unless there > is a valid reason. Indeed I started with something that didn't build and I did the simplest I could to get it build. I agree with you at the end that would be a best, can be done in follow-up patches I guess. > > ... > >>> >>> Including uapi/linux/mman.h may still be problematic on >>> some architectures if they change it in a way that is >>> incompatible with compat vdso, but at least that can't >>> accidentally rely on CONFIG_64BIT or something else that >>> would be wrong there. >> >> Yes that one is tricky. Because uapi/linux/mman.h includes asm/mman.h with the >> intention to include uapi/asm/mman.h but when built from the kernel in reality >> you get arch/powerpc/include/asm/mman.h and I had to add some ifdefery to >> kick-out kernel oddities it contains that pull additional kernel headers. >> >> diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h >> index 17a77d47ed6d..42a51a993d94 100644 >> --- a/arch/powerpc/include/asm/mman.h >> +++ b/arch/powerpc/include/asm/mman.h >> @@ -6,7 +6,7 @@ >> >> #include <uapi/asm/mman.h> >> >> -#ifdef CONFIG_PPC64 >> +#if defined(CONFIG_PPC64) && !defined(BUILD_VDSO) >> >> #include <asm/cputable.h> >> #include <linux/mm.h> >> > > I agree with Arnd here. uapi/linux/mman.h can cause us problems in the long run. Fully agree. > > I am attaching a patch to provide my view on how to minimize the headers > included and use only the vdso/ namespace. Please, before using the code, > consider that I conducted very limited testing. > > Note: It should apply clean on Jason's tree. > > Let me know your thoughts. > >> >> Christophe >
Hi Vicenzo, Le 27/08/2024 à 18:05, Vincenzo Frascino a écrit : > Hi Christophe, > > On 27/08/2024 11:49, Christophe Leroy wrote: > > ... > > > > I agree with Arnd here. uapi/linux/mman.h can cause us problems in the long run. > > I am attaching a patch to provide my view on how to minimize the headers > included and use only the vdso/ namespace. Please, before using the code, > consider that I conducted very limited testing. > > Note: It should apply clean on Jason's tree. > > Let me know your thoughts. > Your patch looks nice, maybe a bit too much. For instance getrandom.c can include directly asm/vdso/page.h instead of creating vdso/page.h Or create a vdso/page.h that only use CONFIG_PAGE_SHIFT and doesn't include anything from architectures. We should also keep PROT_READ and PROT_WRITE in getrandom.c , that's better for readability. Same for MAP_DROPPABLE | MAP_ANONYMOUS. I can't see the benefit of hiding them in a header. I can't see which header provides you with min_t() or ARRAY_SIZE(). I think you should also work on removing headers included by arch/x86/include/asm/vdso/gettimeofday.h which is included by include/vdso/datapage.h : #include <uapi/linux/time.h> #include <asm/vgtod.h> #include <asm/vvar.h> #include <asm/unistd.h> #include <asm/msr.h> #include <asm/pvclock.h> #include <clocksource/hyperv_timer.h> As a comparison, the one from powerpc only includes the following one so it pulls a lot less non-vdso headers: #include <asm/vdso/timebase.h> #include <asm/barrier.h> #include <asm/unistd.h> #include <uapi/linux/time.h> Christophe
Hi Christophe, On 27/08/2024 18:14, Christophe Leroy wrote: > > > Le 27/08/2024 à 18:05, Vincenzo Frascino a écrit : >> Hi Christophe, >> >> On 27/08/2024 11:49, Christophe Leroy wrote: >> >> ... ... >> >> Could you please clarify where minmax is needed? I tried to build Jason's master >> tree for x86, commenting the header and it seems building fine. I might be >> missing something. > > Without it: > > VDSO32C arch/powerpc/kernel/vdso/vgetrandom-32.o > In file included from /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:11, > from <command-line>: ... > > >> >>> Same for ARRAY_SIZE(->reserved) by the way, easy to do opencode, we also have it >>> only once >>> >> >> I have a similar issue to figure out why linux/array_size.h and >> uapi/linux/random.h are needed. It seems that I can build the object without >> them. Could you please explain? > > Without linux/array_size.h: > > VDSO32C arch/powerpc/kernel/vdso/vgetrandom-32.o > In file included from <command-line>: > /home/chleroy/linux-powerpc/lib/vdso/getrandom.c: In function > '__cvdso_getrandom_data': > /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:40: error: implicit If this is the case, those headers should be defined for the powerpc implementation only. The generic implementation should be interpreted as the minimum common denominator in between all the architectures for what concerns the headers.
Hi Christophe, On 27/08/2024 18:38, LEROY Christophe wrote: > Hi Vicenzo, > > Le 27/08/2024 à 18:05, Vincenzo Frascino a écrit : >> Hi Christophe, >> >> On 27/08/2024 11:49, Christophe Leroy wrote: >> >> ... >> >> >> >> I agree with Arnd here. uapi/linux/mman.h can cause us problems in the long run. >> >> I am attaching a patch to provide my view on how to minimize the headers >> included and use only the vdso/ namespace. Please, before using the code, >> consider that I conducted very limited testing. >> >> Note: It should apply clean on Jason's tree. >> >> Let me know your thoughts. >> > > Your patch looks nice, maybe a bit too much. For instance getrandom.c > can include directly asm/vdso/page.h instead of creating vdso/page.h > > Or create a vdso/page.h that only use CONFIG_PAGE_SHIFT and doesn't > include anything from architectures. > IMHO there should be only one place per architecture where PAGE_SIZE and PAGE_MASK are defined. This makes sure that if there is a problem, we do not have multiple places to look into. The indirection helps to keep consistent the namespace and allows for future extension. Similar logic has been used during my original vDSO headers definition and implementation. > We should also keep PROT_READ and PROT_WRITE in getrandom.c , that's > better for readability. Same for MAP_DROPPABLE | MAP_ANONYMOUS. I can't > see the benefit of hiding them in a header. > The idea is not to make the code unreadable but to defer to the architecture the decision of prot and flags avoiding the inclusion of headers coming from the uapi namespace. > I can't see which header provides you with min_t() or ARRAY_SIZE(). > Good point, this needs to be addressed by my patch, I will extend it, do some more testing and post it again next week. > I think you should also work on removing headers included by > arch/x86/include/asm/vdso/gettimeofday.h which is included by > include/vdso/datapage.h : > > #include <uapi/linux/time.h> > #include <asm/vgtod.h> > #include <asm/vvar.h> > #include <asm/unistd.h> > #include <asm/msr.h> > #include <asm/pvclock.h> > #include <clocksource/hyperv_timer.h> > > As a comparison, the one from powerpc only includes the following one so > it pulls a lot less non-vdso headers: > > #include <asm/vdso/timebase.h> > #include <asm/barrier.h> > #include <asm/unistd.h> > #include <uapi/linux/time.h> > > Christophe This does not seem a concern, in fact I believe that the generic vDSO library should not mandate to the architecture how to organize headers. As far as the requirements are satisfied each architecture should be able to define its own naming and conventions independently.
Hi Vincenzo, Le 29/08/2024 à 14:01, Vincenzo Frascino a écrit : > Hi Christophe, > > On 27/08/2024 18:14, Christophe Leroy wrote: >> >> >> Le 27/08/2024 à 18:05, Vincenzo Frascino a écrit : >>> Hi Christophe, >>> >>> On 27/08/2024 11:49, Christophe Leroy wrote: >>> >>> ... > > ... > >>> >>> Could you please clarify where minmax is needed? I tried to build Jason's master >>> tree for x86, commenting the header and it seems building fine. I might be >>> missing something. >> >> Without it: >> >> VDSO32C arch/powerpc/kernel/vdso/vgetrandom-32.o >> In file included from /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:11, >> from <command-line>: > ... > >> >> >>> >>>> Same for ARRAY_SIZE(->reserved) by the way, easy to do opencode, we also have it >>>> only once >>>> >>> >>> I have a similar issue to figure out why linux/array_size.h and >>> uapi/linux/random.h are needed. It seems that I can build the object without >>> them. Could you please explain? >> >> Without linux/array_size.h: >> >> VDSO32C arch/powerpc/kernel/vdso/vgetrandom-32.o >> In file included from <command-line>: >> /home/chleroy/linux-powerpc/lib/vdso/getrandom.c: In function >> '__cvdso_getrandom_data': >> /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:40: error: implicit > If this is the case, those headers should be defined for the powerpc > implementation only. The generic implementation should be interpreted as the > minimum common denominator in between all the architectures for what concerns > the headers. > Sorry, I disagree. You can't rely on necessary headers being included indirectly by other arch specific headers. getrandom.c uses ARRAY_SIZE(), it must include the header that defines ARRAY_SIZE(). At the moment, on x86 you get linux/array.h by change through the following chain, that the reason why the build doesn't break: In file included from ./include/linux/kernel.h:16, from ./include/linux/cpumask.h:11, from ./arch/x86/include/asm/cpumask.h:5, from ./arch/x86/include/asm/msr.h:11, from ./arch/x86/include/asm/vdso/gettimeofday.h:19, from ./include/vdso/datapage.h:164, from arch/x86/entry/vdso/../../../../lib/vdso/getrandom.c:9, From my point of view you can't expect such a chain from each architecture. Christophe
... >>> Without linux/array_size.h: >>> >>> VDSO32C arch/powerpc/kernel/vdso/vgetrandom-32.o >>> In file included from <command-line>: >>> /home/chleroy/linux-powerpc/lib/vdso/getrandom.c: In function >>> '__cvdso_getrandom_data': >>> /home/chleroy/linux-powerpc/lib/vdso/getrandom.c:89:40: error: implicit >> If this is the case, those headers should be defined for the powerpc >> implementation only. The generic implementation should be interpreted as the >> minimum common denominator in between all the architectures for what concerns >> the headers. >> > > Sorry, I disagree. You can't rely on necessary headers being included indirectly > by other arch specific headers. getrandom.c uses ARRAY_SIZE(), it must include > the header that defines ARRAY_SIZE(). > > At the moment, on x86 you get linux/array.h by change through the following > chain, that the reason why the build doesn't break: > > In file included from ./include/linux/kernel.h:16, > from ./include/linux/cpumask.h:11, > from ./arch/x86/include/asm/cpumask.h:5, > from ./arch/x86/include/asm/msr.h:11, > from ./arch/x86/include/asm/vdso/gettimeofday.h:19, > from ./include/vdso/datapage.h:164, > from arch/x86/entry/vdso/../../../../lib/vdso/getrandom.c:9, > > From my point of view you can't expect such a chain from each architecture. > --->8--- > I can't see which header provides you with min_t() or ARRAY_SIZE(). > Good point, this needs to be addressed by my patch, I will extend it, do some more testing and post it again next week. --->8--- As I explained in my other email (snippet above), my patch should address the cases of ARRAY_SIZE() and min_t() which are directly used by getrandom.c. My comment here refers to the cases not directly used by getrandom.c or the Generic vDSO library more in general (if any). Hope this clarifies. > Christophe
diff --git a/lib/vdso/getrandom.c b/lib/vdso/getrandom.c index f1643656d0b0..e5968ed141cb 100644 --- a/lib/vdso/getrandom.c +++ b/lib/vdso/getrandom.c @@ -14,6 +14,11 @@ #include <asm/unaligned.h> #include <uapi/linux/mman.h> +#undef PAGE_SIZE +#undef PAGE_MASK +#define PAGE_SIZE (1UL << CONFIG_PAGE_SHIFT) +#define PAGE_MASK (~(PAGE_SIZE - 1)) + #define MEMCPY_AND_ZERO_SRC(type, dst, src, len) do { \ while (len >= sizeof(type)) { \ __put_unaligned_t(type, __get_unaligned_t(type, src), dst); \
Using PAGE_SIZE and PAGE_MASK in VDSO requires inclusion of page.h and it creates several problems, see commit 8b3843ae3634 ("vdso/datapage: Quick fix - use asm/page-def.h for ARM64") and commit cffaefd15a8f ("vdso: Use CONFIG_PAGE_SHIFT in vdso/datapage.h"). Redefine PAGE_SIZE and PAGE_MASK based on CONFIG_PAGE_SHIFT. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- v3: Use local consts instead of _PAGE_SIZE and _PAGE_MASK macros that are already defined by some architectures. v4: undefine and redefine PAGE_SIZE and PAGE_MASK --- lib/vdso/getrandom.c | 5 +++++ 1 file changed, 5 insertions(+)