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10908 Simplify SMAP relocations with krtld
*** 188,197 ****
--- 188,203 ----
extern void pm_cfb_rele(void);
extern fastboot_info_t newkernel;
/*
+ * Instructions to enable or disable SMAP, respectively.
+ */
+ static const uint8_t clac_instr[3] = { 0x0f, 0x01, 0xca };
+ static const uint8_t stac_instr[3] = { 0x0f, 0x01, 0xcb };
+
+ /*
* Machine dependent code to reboot.
* "mdep" is interpreted as a character pointer; if non-null, it is a pointer
* to a string to be used as the argument string when rebooting.
*
* "invoke_cb" is a boolean. It is set to true when mdboot() can safely
*** 1452,1457 ****
--- 1458,1497 ----
void
plat_dr_disable_capability(uint64_t features)
{
atomic_and_64(&plat_dr_options, ~features);
+ }
+
+ /*
+ * If SMAP is supported, look through hi_calls and inline
+ * calls to smap_enable() to clac and smap_disable() to stac.
+ */
+ void
+ hotinline_smap(hotinline_desc_t *hid)
+ {
+ if (is_x86_feature(x86_featureset, X86FSET_SMAP) == B_FALSE)
+ return;
+
+ if (strcmp(hid->hid_symname, "smap_enable") == 0) {
+ bcopy(clac_instr, (void *)hid->hid_instr_offset,
+ sizeof (clac_instr));
+ } else if (strcmp(hid->hid_symname, "smap_disable") == 0) {
+ bcopy(stac_instr, (void *)hid->hid_instr_offset,
+ sizeof (stac_instr));
+ }
+ }
+
+ /*
+ * Loop through hi_calls and hand off the inlining to
+ * the appropriate calls.
+ */
+ void
+ do_hotinlines(struct module *mp)
+ {
+ for (hotinline_desc_t *hid = mp->hi_calls; hid != NULL;
+ hid = hid->hid_next) {
+ #if !defined(__xpv)
+ hotinline_smap(hid);
+ #endif /* __xpv */
+ }
}