* [PATCH v2] um: Allow building and running on older hosts
@ 2017-05-25 18:36 Florian Fainelli
2017-05-25 19:51 ` Thomas Meyer
2017-07-05 21:32 ` Richard Weinberger
0 siblings, 2 replies; 6+ messages in thread
From: Florian Fainelli @ 2017-05-25 18:36 UTC (permalink / raw)
To: linux-kernel
Cc: elicooper, thomas, Florian Fainelli, Jeff Dike,
Richard Weinberger, Thomas Gleixner, Ingo Molnar, H. Peter Anvin,
maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT),
open list:USER-MODE LINUX (UML), open list:USER-MODE LINUX (UML)
Commit a78ff1112263 ("um: add extended processor state save/restore
support") and b6024b21fec8 ("um: extend fpstate to _xstate to support
YMM registers") forced the use of the x86 FP _xstate and
PTRACE_GETREGSET/SETREGSET. On older hosts, we would neither be able to
build UML nor run it anymore with these two commits applied because we
don't have definitions for struct _xstate nor these two ptrace requests.
We can determine at build time which fp context structure to check
against, just like we can keep using the old i387 fp save/restore if
PTRACE_GETRESET/SETREGSET are not defined.
Fixes: a78ff1112263 ("um: add extended processor state save/restore support")
Fixes: b6024b21fec8 ("um: extend fpstate to _xstate to support YMM registers")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
Changes in v2:
- re-arrange the #ifdef/curly braces to not take the branch
arch/x86/um/os-Linux/registers.c | 12 ++++++++----
arch/x86/um/user-offsets.c | 4 ++++
2 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/arch/x86/um/os-Linux/registers.c b/arch/x86/um/os-Linux/registers.c
index 00f54a91bb4b..28775f55bde2 100644
--- a/arch/x86/um/os-Linux/registers.c
+++ b/arch/x86/um/os-Linux/registers.c
@@ -26,6 +26,7 @@ int save_i387_registers(int pid, unsigned long *fp_regs)
int save_fp_registers(int pid, unsigned long *fp_regs)
{
+#ifdef PTRACE_GETREGSET
struct iovec iov;
if (have_xstate_support) {
@@ -34,9 +35,9 @@ int save_fp_registers(int pid, unsigned long *fp_regs)
if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
return -errno;
return 0;
- } else {
+ } else
+#endif
return save_i387_registers(pid, fp_regs);
- }
}
int restore_i387_registers(int pid, unsigned long *fp_regs)
@@ -48,6 +49,7 @@ int restore_i387_registers(int pid, unsigned long *fp_regs)
int restore_fp_registers(int pid, unsigned long *fp_regs)
{
+#ifdef PTRACE_SETREGSET
struct iovec iov;
if (have_xstate_support) {
@@ -56,9 +58,9 @@ int restore_fp_registers(int pid, unsigned long *fp_regs)
if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
return -errno;
return 0;
- } else {
+ } else
+#endif
return restore_i387_registers(pid, fp_regs);
- }
}
#ifdef __i386__
@@ -122,6 +124,7 @@ int put_fp_registers(int pid, unsigned long *regs)
void arch_init_registers(int pid)
{
+#ifdef PTRACE_GETREGSET
struct _xstate fp_regs;
struct iovec iov;
@@ -129,6 +132,7 @@ void arch_init_registers(int pid)
iov.iov_len = sizeof(struct _xstate);
if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) == 0)
have_xstate_support = 1;
+#endif
}
#endif
diff --git a/arch/x86/um/user-offsets.c b/arch/x86/um/user-offsets.c
index cb3c22370cf5..8af0fb5d2780 100644
--- a/arch/x86/um/user-offsets.c
+++ b/arch/x86/um/user-offsets.c
@@ -50,7 +50,11 @@ void foo(void)
DEFINE(HOST_GS, GS);
DEFINE(HOST_ORIG_AX, ORIG_EAX);
#else
+#if defined(PTRACE_GETREGSET) && defined(PTRACE_SETREGSET)
DEFINE(HOST_FP_SIZE, sizeof(struct _xstate) / sizeof(unsigned long));
+#else
+ DEFINE(HOST_FP_SIZE, sizeof(struct _fpstate) / sizeof(unsigned long));
+#endif
DEFINE_LONGS(HOST_BX, RBX);
DEFINE_LONGS(HOST_CX, RCX);
DEFINE_LONGS(HOST_DI, RDI);
--
2.12.2
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] um: Allow building and running on older hosts
2017-05-25 18:36 [PATCH v2] um: Allow building and running on older hosts Florian Fainelli
@ 2017-05-25 19:51 ` Thomas Meyer
2017-05-25 22:28 ` Florian Fainelli
2017-07-05 21:32 ` Richard Weinberger
1 sibling, 1 reply; 6+ messages in thread
From: Thomas Meyer @ 2017-05-25 19:51 UTC (permalink / raw)
To: Florian Fainelli
Cc: linux-kernel, elicooper, Jeff Dike, Richard Weinberger,
Thomas Gleixner, Ingo Molnar, H. Peter Anvin,
maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT),
open list:USER-MODE LINUX (UML), open list:USER-MODE LINUX (UML)
[-- Attachment #1: Type: text/plain, Size: 3940 bytes --]
> Am 25.05.2017 um 20:36 schrieb Florian Fainelli <f.fainelli@gmail.com>:
>
> Commit a78ff1112263 ("um: add extended processor state save/restore
> support") and b6024b21fec8 ("um: extend fpstate to _xstate to support
> YMM registers") forced the use of the x86 FP _xstate and
> PTRACE_GETREGSET/SETREGSET. On older hosts, we would neither be able to
> build UML nor run it anymore with these two commits applied because we
> don't have definitions for struct _xstate nor these two ptrace requests.
Btw. what soy you mean with older host? I need to revert two commits to make an UML kernel work again on a Fedora 25 installation.
>
> We can determine at build time which fp context structure to check
> against, just like we can keep using the old i387 fp save/restore if
> PTRACE_GETRESET/SETREGSET are not defined.
>
> Fixes: a78ff1112263 ("um: add extended processor state save/restore support")
> Fixes: b6024b21fec8 ("um: extend fpstate to _xstate to support YMM registers")
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
> ---
> Changes in v2:
>
> - re-arrange the #ifdef/curly braces to not take the branch
>
> arch/x86/um/os-Linux/registers.c | 12 ++++++++----
> arch/x86/um/user-offsets.c | 4 ++++
> 2 files changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/um/os-Linux/registers.c b/arch/x86/um/os-Linux/registers.c
> index 00f54a91bb4b..28775f55bde2 100644
> --- a/arch/x86/um/os-Linux/registers.c
> +++ b/arch/x86/um/os-Linux/registers.c
> @@ -26,6 +26,7 @@ int save_i387_registers(int pid, unsigned long *fp_regs)
>
> int save_fp_registers(int pid, unsigned long *fp_regs)
> {
> +#ifdef PTRACE_GETREGSET
> struct iovec iov;
>
> if (have_xstate_support) {
> @@ -34,9 +35,9 @@ int save_fp_registers(int pid, unsigned long *fp_regs)
> if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
> return -errno;
> return 0;
> - } else {
> + } else
> +#endif
> return save_i387_registers(pid, fp_regs);
> - }
> }
>
> int restore_i387_registers(int pid, unsigned long *fp_regs)
> @@ -48,6 +49,7 @@ int restore_i387_registers(int pid, unsigned long *fp_regs)
>
> int restore_fp_registers(int pid, unsigned long *fp_regs)
> {
> +#ifdef PTRACE_SETREGSET
> struct iovec iov;
>
> if (have_xstate_support) {
> @@ -56,9 +58,9 @@ int restore_fp_registers(int pid, unsigned long *fp_regs)
> if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
> return -errno;
> return 0;
> - } else {
> + } else
> +#endif
> return restore_i387_registers(pid, fp_regs);
> - }
> }
>
> #ifdef __i386__
> @@ -122,6 +124,7 @@ int put_fp_registers(int pid, unsigned long *regs)
>
> void arch_init_registers(int pid)
> {
> +#ifdef PTRACE_GETREGSET
> struct _xstate fp_regs;
> struct iovec iov;
>
> @@ -129,6 +132,7 @@ void arch_init_registers(int pid)
> iov.iov_len = sizeof(struct _xstate);
> if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) == 0)
> have_xstate_support = 1;
In my setup above call works correctly and so have_xstate_support will be set, but save_fp_registers fails with errno 4 or so...
> +#endif
> }
> #endif
>
> diff --git a/arch/x86/um/user-offsets.c b/arch/x86/um/user-offsets.c
> index cb3c22370cf5..8af0fb5d2780 100644
> --- a/arch/x86/um/user-offsets.c
> +++ b/arch/x86/um/user-offsets.c
> @@ -50,7 +50,11 @@ void foo(void)
> DEFINE(HOST_GS, GS);
> DEFINE(HOST_ORIG_AX, ORIG_EAX);
> #else
> +#if defined(PTRACE_GETREGSET) && defined(PTRACE_SETREGSET)
> DEFINE(HOST_FP_SIZE, sizeof(struct _xstate) / sizeof(unsigned long));
> +#else
> + DEFINE(HOST_FP_SIZE, sizeof(struct _fpstate) / sizeof(unsigned long));
> +#endif
> DEFINE_LONGS(HOST_BX, RBX);
> DEFINE_LONGS(HOST_CX, RCX);
> DEFINE_LONGS(HOST_DI, RDI);
> --
> 2.12.2
>
[-- Attachment #2: smime.p7s --]
[-- Type: application/pkcs7-signature, Size: 5334 bytes --]
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] um: Allow building and running on older hosts
2017-05-25 19:51 ` Thomas Meyer
@ 2017-05-25 22:28 ` Florian Fainelli
2017-05-25 22:34 ` Richard Weinberger
0 siblings, 1 reply; 6+ messages in thread
From: Florian Fainelli @ 2017-05-25 22:28 UTC (permalink / raw)
To: Thomas Meyer
Cc: linux-kernel, elicooper, Jeff Dike, Richard Weinberger,
Thomas Gleixner, Ingo Molnar, H. Peter Anvin,
maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT),
open list:USER-MODE LINUX (UML), open list:USER-MODE LINUX (UML)
On 05/25/2017 12:51 PM, Thomas Meyer wrote:
>
>> Am 25.05.2017 um 20:36 schrieb Florian Fainelli <f.fainelli@gmail.com>:
>>
>> Commit a78ff1112263 ("um: add extended processor state save/restore
>> support") and b6024b21fec8 ("um: extend fpstate to _xstate to support
>> YMM registers") forced the use of the x86 FP _xstate and
>> PTRACE_GETREGSET/SETREGSET. On older hosts, we would neither be able to
>> build UML nor run it anymore with these two commits applied because we
>> don't have definitions for struct _xstate nor these two ptrace requests.
>
> Btw. what soy you mean with older host? I need to revert two commits to make an UML kernel work again on a Fedora 25 installation.
This is centos 6.9, so kernel 2.6.32 and glibc 2.12, this neither has
xstate nor PTRACE_GETREGSET/SETREGSET, hence this patch.
>
>>
>> We can determine at build time which fp context structure to check
>> against, just like we can keep using the old i387 fp save/restore if
>> PTRACE_GETRESET/SETREGSET are not defined.
>>
>> Fixes: a78ff1112263 ("um: add extended processor state save/restore support")
>> Fixes: b6024b21fec8 ("um: extend fpstate to _xstate to support YMM registers")
>> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
>> ---
>> Changes in v2:
>>
>> - re-arrange the #ifdef/curly braces to not take the branch
>>
>> arch/x86/um/os-Linux/registers.c | 12 ++++++++----
>> arch/x86/um/user-offsets.c | 4 ++++
>> 2 files changed, 12 insertions(+), 4 deletions(-)
>>
>> diff --git a/arch/x86/um/os-Linux/registers.c b/arch/x86/um/os-Linux/registers.c
>> index 00f54a91bb4b..28775f55bde2 100644
>> --- a/arch/x86/um/os-Linux/registers.c
>> +++ b/arch/x86/um/os-Linux/registers.c
>> @@ -26,6 +26,7 @@ int save_i387_registers(int pid, unsigned long *fp_regs)
>>
>> int save_fp_registers(int pid, unsigned long *fp_regs)
>> {
>> +#ifdef PTRACE_GETREGSET
>> struct iovec iov;
>>
>> if (have_xstate_support) {
>> @@ -34,9 +35,9 @@ int save_fp_registers(int pid, unsigned long *fp_regs)
>> if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
>> return -errno;
>> return 0;
>> - } else {
>> + } else
>> +#endif
>> return save_i387_registers(pid, fp_regs);
>> - }
>> }
>>
>> int restore_i387_registers(int pid, unsigned long *fp_regs)
>> @@ -48,6 +49,7 @@ int restore_i387_registers(int pid, unsigned long *fp_regs)
>>
>> int restore_fp_registers(int pid, unsigned long *fp_regs)
>> {
>> +#ifdef PTRACE_SETREGSET
>> struct iovec iov;
>>
>> if (have_xstate_support) {
>> @@ -56,9 +58,9 @@ int restore_fp_registers(int pid, unsigned long *fp_regs)
>> if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
>> return -errno;
>> return 0;
>> - } else {
>> + } else
>> +#endif
>> return restore_i387_registers(pid, fp_regs);
>> - }
>> }
>>
>> #ifdef __i386__
>> @@ -122,6 +124,7 @@ int put_fp_registers(int pid, unsigned long *regs)
>>
>> void arch_init_registers(int pid)
>> {
>> +#ifdef PTRACE_GETREGSET
>> struct _xstate fp_regs;
>> struct iovec iov;
>>
>> @@ -129,6 +132,7 @@ void arch_init_registers(int pid)
>> iov.iov_len = sizeof(struct _xstate);
>> if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) == 0)
>> have_xstate_support = 1;
>
> In my setup above call works correctly and so have_xstate_support will be set, but save_fp_registers fails with errno 4 or so...
>
>> +#endif
>> }
>> #endif
>>
>> diff --git a/arch/x86/um/user-offsets.c b/arch/x86/um/user-offsets.c
>> index cb3c22370cf5..8af0fb5d2780 100644
>> --- a/arch/x86/um/user-offsets.c
>> +++ b/arch/x86/um/user-offsets.c
>> @@ -50,7 +50,11 @@ void foo(void)
>> DEFINE(HOST_GS, GS);
>> DEFINE(HOST_ORIG_AX, ORIG_EAX);
>> #else
>> +#if defined(PTRACE_GETREGSET) && defined(PTRACE_SETREGSET)
>> DEFINE(HOST_FP_SIZE, sizeof(struct _xstate) / sizeof(unsigned long));
>> +#else
>> + DEFINE(HOST_FP_SIZE, sizeof(struct _fpstate) / sizeof(unsigned long));
>> +#endif
>> DEFINE_LONGS(HOST_BX, RBX);
>> DEFINE_LONGS(HOST_CX, RCX);
>> DEFINE_LONGS(HOST_DI, RDI);
>> --
>> 2.12.2
>>
--
Florian
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] um: Allow building and running on older hosts
2017-05-25 22:28 ` Florian Fainelli
@ 2017-05-25 22:34 ` Richard Weinberger
2017-06-01 20:40 ` Florian Fainelli
0 siblings, 1 reply; 6+ messages in thread
From: Richard Weinberger @ 2017-05-25 22:34 UTC (permalink / raw)
To: Florian Fainelli, Thomas Meyer
Cc: linux-kernel, elicooper, Jeff Dike, Thomas Gleixner, Ingo Molnar,
H. Peter Anvin, maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT),
open list:USER-MODE LINUX (UML), open list:USER-MODE LINUX (UML)
Thomas, Florian,
Am 26.05.2017 um 00:28 schrieb Florian Fainelli:
> On 05/25/2017 12:51 PM, Thomas Meyer wrote:
>>
>>> Am 25.05.2017 um 20:36 schrieb Florian Fainelli <f.fainelli@gmail.com>:
>>>
>>> Commit a78ff1112263 ("um: add extended processor state save/restore
>>> support") and b6024b21fec8 ("um: extend fpstate to _xstate to support
>>> YMM registers") forced the use of the x86 FP _xstate and
>>> PTRACE_GETREGSET/SETREGSET. On older hosts, we would neither be able to
>>> build UML nor run it anymore with these two commits applied because we
>>> don't have definitions for struct _xstate nor these two ptrace requests.
>>
>> Btw. what soy you mean with older host? I need to revert two commits to make an UML kernel work again on a Fedora 25 installation.
>
> This is centos 6.9, so kernel 2.6.32 and glibc 2.12, this neither has
> xstate nor PTRACE_GETREGSET/SETREGSET, hence this patch.
Commits a78ff1112263 and b6024b21fec8 are broken.
You see two different issues.
Eli, please have a look too.
Thanks,
//richard
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] um: Allow building and running on older hosts
2017-05-25 22:34 ` Richard Weinberger
@ 2017-06-01 20:40 ` Florian Fainelli
0 siblings, 0 replies; 6+ messages in thread
From: Florian Fainelli @ 2017-06-01 20:40 UTC (permalink / raw)
To: Richard Weinberger, Thomas Meyer, elicooper
Cc: linux-kernel, Jeff Dike, Thomas Gleixner, Ingo Molnar,
H. Peter Anvin, maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT),
open list:USER-MODE LINUX (UML), open list:USER-MODE LINUX (UML)
On 05/25/2017 03:34 PM, Richard Weinberger wrote:
> Thomas, Florian,
>
> Am 26.05.2017 um 00:28 schrieb Florian Fainelli:
>> On 05/25/2017 12:51 PM, Thomas Meyer wrote:
>>>
>>>> Am 25.05.2017 um 20:36 schrieb Florian Fainelli <f.fainelli@gmail.com>:
>>>>
>>>> Commit a78ff1112263 ("um: add extended processor state save/restore
>>>> support") and b6024b21fec8 ("um: extend fpstate to _xstate to support
>>>> YMM registers") forced the use of the x86 FP _xstate and
>>>> PTRACE_GETREGSET/SETREGSET. On older hosts, we would neither be able to
>>>> build UML nor run it anymore with these two commits applied because we
>>>> don't have definitions for struct _xstate nor these two ptrace requests.
>>>
>>> Btw. what soy you mean with older host? I need to revert two commits to make an UML kernel work again on a Fedora 25 installation.
>>
>> This is centos 6.9, so kernel 2.6.32 and glibc 2.12, this neither has
>> xstate nor PTRACE_GETREGSET/SETREGSET, hence this patch.
>
> Commits a78ff1112263 and b6024b21fec8 are broken.
> You see two different issues.
> Eli, please have a look too.
Eli, can we get an answer here? And Thomas what's that problem that
Richard is referring to?
--
Florian
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] um: Allow building and running on older hosts
2017-05-25 18:36 [PATCH v2] um: Allow building and running on older hosts Florian Fainelli
2017-05-25 19:51 ` Thomas Meyer
@ 2017-07-05 21:32 ` Richard Weinberger
1 sibling, 0 replies; 6+ messages in thread
From: Richard Weinberger @ 2017-07-05 21:32 UTC (permalink / raw)
To: Florian Fainelli
Cc: LKML, elicooper, Thomas Meyer, Jeff Dike, Richard Weinberger,
Thomas Gleixner, Ingo Molnar, H. Peter Anvin,
maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT),
open list:USER-MODE LINUX (UML), open list:USER-MODE LINUX (UML)
Florian,
On Thu, May 25, 2017 at 8:36 PM, Florian Fainelli <f.fainelli@gmail.com> wrote:
> Commit a78ff1112263 ("um: add extended processor state save/restore
> support") and b6024b21fec8 ("um: extend fpstate to _xstate to support
> YMM registers") forced the use of the x86 FP _xstate and
> PTRACE_GETREGSET/SETREGSET. On older hosts, we would neither be able to
> build UML nor run it anymore with these two commits applied because we
> don't have definitions for struct _xstate nor these two ptrace requests.
>
> We can determine at build time which fp context structure to check
> against, just like we can keep using the old i387 fp save/restore if
> PTRACE_GETRESET/SETREGSET are not defined.
>
> Fixes: a78ff1112263 ("um: add extended processor state save/restore support")
> Fixes: b6024b21fec8 ("um: extend fpstate to _xstate to support YMM registers")
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Both patches applied. Thanks a lot for fixing these regressions!
--
Thanks,
//richard
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-07-05 21:32 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-05-25 18:36 [PATCH v2] um: Allow building and running on older hosts Florian Fainelli
2017-05-25 19:51 ` Thomas Meyer
2017-05-25 22:28 ` Florian Fainelli
2017-05-25 22:34 ` Richard Weinberger
2017-06-01 20:40 ` Florian Fainelli
2017-07-05 21:32 ` Richard Weinberger
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®