Update to efivar 34, and include a patch to avoid upstream rate limiting.

Signed-off-by: Peter Jones <pjones@redhat.com>

0001-efivarfs-vars-usleep-before-reading-from-efivarfs-if.patch

@@ -0,0 +1,117 @@
+From 5ea8c3400693b30c2b65a887899dc2a8e36a9688 Mon Sep 17 00:00:00 2001
+From: Peter Jones <pjones@redhat.com>
+Date: Fri, 23 Feb 2018 15:49:02 -0500
+Subject: [PATCH] efivarfs / vars: usleep() before reading from efivarfs if
+ euid != 0
+
+There's a kernel rate limiter on efi variable reads now for
+non-root users, and we'd rather just not hit it than have to dig out
+from having hit it.  So this adds a 10ms sleep before each read call.
+
+If you do have 50 variables, efibootmgr will do 100 reads, which would
+trigger the rate limit.  In that case, this patch adds 1 second (plus
+lossage due to calling, etc.), so it should stay just below the
+triggering threshold.  That will definitely be /smoother/ than hitting
+it, and almost certainly faster as well, because the extra calls will
+re-enforce the limit.
+
+Signed-off-by: Peter Jones <pjones@redhat.com>
+---
+ src/efivarfs.c | 12 ++++++++++++
+ src/vars.c     | 11 +++++++++++
+ src/util.h     |  7 +++++++
+ 3 files changed, 30 insertions(+)
+
+diff --git a/src/efivarfs.c b/src/efivarfs.c
+index d1458a24d1e..38e4074e977 100644
+--- a/src/efivarfs.c
++++ b/src/efivarfs.c
+@@ -220,6 +220,16 @@ efivarfs_get_variable(efi_guid_t guid, const char *name, uint8_t **data,
+ 	int fd = -1;
+ 	char *path = NULL;
+ 	int rc;
++	int ratelimit;
++
++	/*
++	 * The kernel rate limiter hits us if we go faster than 100 efi
++	 * variable reads per second as non-root.  So if we're not root, just
++	 * delay this long after each read.  The user is not going to notice.
++	 *
++	 * 1s / 100 = 10000us.
++	 */
++	ratelimit = geteuid() == 0 ? 0 : 10000;
+ 
+ 	rc = make_efivarfs_path(&path, guid, name);
+ 	if (rc < 0) {
+@@ -233,12 +243,14 @@ efivarfs_get_variable(efi_guid_t guid, const char *name, uint8_t **data,
+ 		goto err;
+ 	}
+ 
++	usleep(ratelimit);
+ 	rc = read(fd, &ret_attributes, sizeof (ret_attributes));
+ 	if (rc < 0) {
+ 		efi_error("read failed");
+ 		goto err;
+ 	}
+ 
++	usleep(ratelimit);
+ 	rc = read_file(fd, &ret_data, &size);
+ 	if (rc < 0) {
+ 		efi_error("read_file failed");
+diff --git a/src/vars.c b/src/vars.c
+index a7b5e2387f9..8522725a51f 100644
+--- a/src/vars.c
++++ b/src/vars.c
+@@ -305,6 +305,16 @@ vars_get_variable(efi_guid_t guid, const char *name, uint8_t **data,
+ 	char *path = NULL;
+ 	int rc;
+ 	int fd = -1;
++	int ratelimit;
++
++	/*
++	 * The kernel rate limiter hits us if we go faster than 100 efi
++	 * variable reads per second as non-root.  So if we're not root, just
++	 * delay this long after each read.  The user is not going to notice.
++	 *
++	 * 1s / 100 = 10000us.
++	 */
++	ratelimit = geteuid() == 0 ? 0 : 10000;
+ 
+ 	rc = asprintf(&path, "%s%s-" GUID_FORMAT "/raw_var",
+ 			  get_vars_path(),
+@@ -322,6 +332,7 @@ vars_get_variable(efi_guid_t guid, const char *name, uint8_t **data,
+ 		goto err;
+ 	}
+ 
++	usleep(ratelimit);
+ 	rc = read_file(fd, &buf, &bufsize);
+ 	if (rc < 0) {
+ 		efi_error("read_file(%s) failed", path);
+diff --git a/src/util.h b/src/util.h
+index deef7e71bc4..69042d3cf9a 100644
+--- a/src/util.h
++++ b/src/util.h
+@@ -25,6 +25,7 @@
+ #include <endian.h>
+ #include <errno.h>
+ #include <limits.h>
++#include <sched.h>
+ #include <stdio.h>
+ #include <stdarg.h>
+ #include <stdlib.h>
+@@ -137,6 +138,12 @@ read_file(int fd, uint8_t **buf, size_t *bufsize)
+ 		 * before doing so. */
+ 		s = read(fd, p, size - filesize);
+ 		if (s < 0 && errno == EAGAIN) {
++			/*
++			 * if we got EAGAIN, there's a good chance we've hit
++			 * the kernel rate limiter.  Doing more reads is just
++			 * going to make it worse, so instead, give it a rest.
++			 */
++			sched_yield();
+ 			continue;
+ 		} else if (s < 0) {
+ 			int saved_errno = errno;
+-- 
+2.15.0
+

efivar.spec

@@ -1,6 +1,6 @@
 Name:           efivar
-Version:        33
-Release:        3%{?dist}
+Version:        34
+Release:        1%{?dist}
 Summary:        Tools to manage UEFI variables
 License:        LGPLv2.1
 URL:            https://github.com/rhboot/efivar
@@ -8,7 +8,10 @@ Requires:       %{name}-libs = %{version}-%{release}
 ExclusiveArch:  %{ix86} x86_64 aarch64 %{arm}
 
 BuildRequires:  popt-devel git glibc-static libabigail
-Source0:        https://github.com/rhboot/efivar/archive/%{version}.tar.bz2
+# please don't fix this to reflect github's incomprehensible url that goes
+# to a different tarball.
+Source0:        https://github.com/rhboot/efivar/archive/efivar-%{version}.tar.bz2
+Patch0001:	0001-efivarfs-vars-usleep-before-reading-from-efivarfs-if.patch
 
 %description
 efivar provides a simple command line interface to the UEFI variable facility.
@@ -70,6 +73,9 @@ make libdir=%{_libdir} bindir=%{_bindir} CFLAGS="$RPM_OPT_FLAGS -flto" LDFLAGS="
 %{_libdir}/*.so.*
 
 %changelog
+* Tue Feb 27 2018 Peter Jones <pjones@redhat.com> - 34-1
+- Update to efivar 34, and include a patch to avoid upstream rate limiting.
+
 * Wed Feb 07 2018 Fedora Release Engineering <releng@fedoraproject.org> - 33-3
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_28_Mass_Rebuild
 

sources

@@ -1 +1 @@
-SHA512 (33.tar.bz2) = 76c053b38b6293e79eff2dcaaaed35c87e875fb7ab67163f91190085c2733c105b351d062b6f95786f95597396be5137284ab7537ba8b9968da4b648247862f3
+SHA512 (efivar-34.tar.bz2) = 6baa02e1ad919f84d129a032a4631126d6f43dfc247f63c247624cc2af697fb627fd76fe0ffed069b42b835d862582877644fb19843361ef9ced62aa7cd518c4