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| author | Reinette Chatre <reinette.chatre@intel.com> | 2018-12-10 14:31:13 -0800 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2018-12-11 22:09:28 +0100 |
| commit | 52eb74339a6233c69f4e3794b69ea7c98eeeae1b (patch) | |
| tree | c309a778e340dc47f89d7e9abee5f2932597a4cc | |
| parent | cb74635faa17cfa2991ddbe027596270af525c6d (diff) | |
| download | linux-52eb74339a6233c69f4e3794b69ea7c98eeeae1b.tar.bz2 | |
x86/resctrl: Fix rdt_find_domain() return value and checks
rdt_find_domain() returns an ERR_PTR() that is generated from a provided
domain id when the value is negative.
Care needs to be taken when creating an ERR_PTR() from this value
because a subsequent check using IS_ERR() expects the error to
be within the MAX_ERRNO range. Using an invalid domain id as an
ERR_PTR() does work at this time since this is currently always -1.
Using this undocumented assumption is fragile since future users of
rdt_find_domain() may not be aware of thus assumption.
Two related issues are addressed:
- Ensure that rdt_find_domain() always returns a valid error value by
forcing the error to be -ENODEV when a negative domain id is provided.
- In a few instances the return value of rdt_find_domain() is just
checked for NULL - fix these to include a check of ERR_PTR.
Fixes: d89b7379015f ("x86/intel_rdt/cqm: Add mon_data")
Fixes: 521348b011d6 ("x86/intel_rdt: Introduce utility to obtain CDP peer")
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: fenghua.yu@intel.com
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/b88cd4ff6a75995bf8db9b0ea546908fe50f69f3.1544479852.git.reinette.chatre@intel.com
| -rw-r--r-- | arch/x86/kernel/cpu/resctrl/core.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/resctrl/rdtgroup.c | 2 |
3 files changed, 3 insertions, 3 deletions
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index 2ec252be4ed9..c3a9dc63edf2 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -454,7 +454,7 @@ struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id, struct list_head *l; if (id < 0) - return ERR_PTR(id); + return ERR_PTR(-ENODEV); list_for_each(l, &r->domains) { d = list_entry(l, struct rdt_domain, list); diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c index ba11f54f5ab8..3b943ace786c 100644 --- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c +++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c @@ -534,7 +534,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg) r = &rdt_resources_all[resid]; d = rdt_find_domain(r, domid, NULL); - if (!d) { + if (IS_ERR_OR_NULL(d)) { ret = -ENOENT; goto out; } diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 017505017bdb..8388adf241b2 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -1029,7 +1029,7 @@ static int rdt_cdp_peer_get(struct rdt_resource *r, struct rdt_domain *d, * peer RDT CDP resource. Hence the WARN. */ _d_cdp = rdt_find_domain(_r_cdp, d->id, NULL); - if (WARN_ON(!_d_cdp)) { + if (WARN_ON(IS_ERR_OR_NULL(_d_cdp))) { _r_cdp = NULL; ret = -EINVAL; } |