UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

- Prevent unintentional page sharing by checking whether a page 

reference to a PMU samples page has been acquired properly before that
 
 - Make sure the LBR_SELECT MSR is saved/restored too
 
 - Reset the LBR_SELECT MSR when resetting the LBR PMU to clear any
 residual data left
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmGQ5z8ACgkQEsHwGGHe
 VUqqdQ/+JIV6t0yIj7aNADaakwAe+i9zFzzUuvb5KT0zPzZirswkz6xeZ4g8S8PZ
 lSjqKk8M2Yt3SJiqi/s3KNIOev52wtKGmeOFz1I+DUNpgk0wGHkRtVHV/iSptB61
 Kp/fJvOVppY5grs5B0fRYkM5e477RPyZo+E0COKnff1bQ+k+z2ItMLCVxFCxQS6k
 HmgPW7CBye811YcEg28lSwgS1OXiMZ19gACIsqnQ6kQP2Puo8+HT1/V1n+0grejb
 OeYxURuYSRPd6Ft76qz0YlRIe1dgKllUBr7b0AaM11ADBMtWBTxqJcQvq/mOIHmT
 9to0dVB/xFySR57iaL7BRuZFOrt8MRqJniEedMO99Dm9sxEVfHs1iXC9r7wZxQAf
 /HcvVkcyOJD92Kv+4LS5tKjowCByOYEJW2YQIgXEbA6oIhRuM9/fdxEW6lHwgdwc
 BPnOR6rtYuq+I+merBIIijAuf8OsIGY7ap2B+f7DkiOtA9+SHZsrU22J8T7CED/w
 gmrAC3+3KGt7YDs6WZTbvkXminZQyu5WpHe+2K6dlCIPmJLqEsYUx8TeXa/okyvb
 8ZXy/CfJNbHUrk6GZw7RFoeannwSPv9ZJO3Mfy5PDvwDk0Fj0J+/G92mR2Zucxpo
 siNyBCivPY5vBPqk+x6eUPev/C3wPS+dNrs4HOyr1N2gZwgTk40=
 =Ciqw
 -----END PGP SIGNATURE-----

Merge tag 'perf_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Borislav Petkov:

 - Prevent unintentional page sharing by checking whether a page
   reference to a PMU samples page has been acquired properly before
   that

 - Make sure the LBR_SELECT MSR is saved/restored too

 - Reset the LBR_SELECT MSR when resetting the LBR PMU to clear any
   residual data left

* tag 'perf_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Avoid put_page() when GUP fails
  perf/x86/vlbr: Add c->flags to vlbr event constraints
  perf/x86/lbr: Reset LBR_SELECT during vlbr reset
This commit is contained in:
Linus Torvalds 2021-11-14 09:33:12 -08:00
parent 1654e95ee3 4716023a8f
commit f7018be292
3 changed files with 10 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/x86/events/intel/core.c
View File

@ -3048,8 +3048,10 @@ intel_vlbr_constraints(struct perf_event *event)
{
struct event_constraint *c = &vlbr_constraint;
if (unlikely(constraint_match(c, event->hw.config)))
if (unlikely(constraint_match(c, event->hw.config))) {
event->hw.flags |= c->flags;
return c;
}
return NULL;
}

2
arch/x86/events/intel/lbr.c
View File

@ -265,6 +265,8 @@ void intel_pmu_lbr_reset(void)
cpuc->last_task_ctx = NULL;
cpuc->last_log_id = 0;
if (!static_cpu_has(X86_FEATURE_ARCH_LBR) && cpuc->lbr_select)
wrmsrl(MSR_LBR_SELECT, 0);
}
/*

10
kernel/events/core.c
View File

@ -7154,7 +7154,6 @@ void perf_output_sample(struct perf_output_handle *handle,
static u64 perf_virt_to_phys(u64 virt)
{
u64 phys_addr = 0;
struct page *p = NULL;
if (!virt)
return 0;
@ -7173,14 +7172,15 @@ static u64 perf_virt_to_phys(u64 virt)
* If failed, leave phys_addr as 0.
*/
if (current->mm != NULL) {
struct page *p;
pagefault_disable();
if (get_user_page_fast_only(virt, 0, &p))
if (get_user_page_fast_only(virt, 0, &p)) {
phys_addr = page_to_phys(p) + virt % PAGE_SIZE;
put_page(p);
}
pagefault_enable();
}
if (p)
put_page(p);
}
return phys_addr;